XSS (Cross Site Scripting) Cheat Sheet

来源：百度文库编辑：神马文学网时间：2024/04/28 04:48:50

Esp: for filter evasion
ByRSnake
Note from the author: XSS is Cross Site Scripting. If you don‘t know how XSS (Cross Site Scripting) works, this page probably won‘t help you. This page is for people who already understand the basics of XSS attacks but want a deep understanding of the nuances regarding filter evasion. This page will also not show you how to mitigate XSS vectors or how to write the actual cookie/credential stealing/replay/session riding portion of the attack. It will simply show the underlying methodology and you can infer the rest. Also, please note my XSS page has been replicated by theOWASP 2.0 Guide in the Appendix section with my permission. However, because this is a living document I suggest you continue to use this site to stay up to date.
Also, please note that most of these cross site scripting vectors have been tested in the browsers listed at the bottom of the page, however, if you have specific concerns about outdated or obscure versions please download them fromEvolt. Please see theXML format of the XSS Cheat Sheet if you intend to useCAL9000 or other automated tools. If you have an RSS reader feel free to subscribe to the Web Application Security RSS feed below, or join theforum:

XSS (Cross Site Scripting): . Inject this string, and in most cases where a script is vulnerable with no special XSS vector requirements the word "XSS" will pop up. Use theURL encoding calculator below to encode the entire string. Tip: if you‘re in a rush and need to quickly check a page, often times injecting the depreciated "" tag will be enough to check to see if something is vulnerable to XSS by messing up the output appreciably: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] . If you don‘t have much space and know there is no vulnerable JavaScript on the page, this string is a nice compact XSS injection check. View source after injecting it and look for <XSS verses <XSS to see if it is vulnerable: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] . This is a normal XSS JavaScript injection, and most likely to get caught but I suggest trying it first (the quotes are not required in any modern browser so they are omitted here): Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] using the JavaScript directive (IE7.0 doesn‘t support the JavaScript directive in context of an image, but it does in other contexts, but the following show the principles that would work in other tags as well - I‘ll probably revise this at a later date): Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] : Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] XSS attack vector: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] (the semicolons are required for this to work): Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] obfuscation (If you need to use both double and single quotes you can use a grave accent to encapsulate the JavaScript string - this is also useful because lots of cross site scripting filters don‘t know about grave accents): Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] . Originally found byBegeek (but cleaned up and shortened to work in all browsers), this XSS vector uses the relaxed rendering engine to create our XSS vector within an IMG tag that should be encapsulated within quotes. I assume this was originally meant to correct sloppy coding. This would make it significantly more difficult to correctly parse apart an HTML tag: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] (if no quotes of any kind are allowed you can eval() a fromCharCode in JavaScript to create any XSS vector you need): Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] encoding (all of the XSS examples that use a javascript: directive inside of an <IMG tag will not work in Firefox or Netscape 8.1+ in the Gecko rendering engine mode). Use theXSS calculator for more information: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] encoding without semicolons (this is often effective in XSS that attempts to look for "&#XX;", since most people don‘t know about padding - up to 7 numeric characters total). This is also useful against people who decode against strings like $tmp_string =~ s/.*\&#(\d+);.*/$1/; which incorrectly assumes a semicolon is required to terminate a html encoded string (I‘ve seen this in the wild): Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] without semicolons (this is also a viable XSS attack against the above string $tmp_string =~ s/.*\&#(\d+);.*/$1/; which assumes that there is a numeric character following the pound symbol - which is not true with hex HTML characters). Use theXSS calculator for more information: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] to break up the cross site scripting attack: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] to break up XSS. For some reason Opera does not allow the encoded tab, but it does allow the previous tab XSS and encoded newline and carriage returns below: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] to break up XSS. Some websites claim that any of the chars 09-13 (decimal) will work for this attack. That is incorrect. Only 09 (horizontal tab), 10 (newline) and 13 (carriage return) work. See theascii chart for more details. The following four XSS examples illustrate this vector: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] to break up XSS (Note: with the above I am making these strings longer than they have to be because the zeros could be omitted. Often I‘ve seen filters that assume the hex and dec encoding has to be two or three characters. The real rule is 1-7 characters.): Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] Injected JavaScript using ASCII carriage returns (same as above only a more extreme example of this XSS vector) these are not spaces just one of the three characters as described above: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] breaks up JavaScript directive. Okay, I lied, null chars also work as XSS vectors but not like above, you need to inject them directly using something likeBurp Proxy or use %00 in the URL string or if you want to write your own injection tool you can either usevim (^V^@ will produce a null) or the following program to generate it into a text file. Okay, I lied again, older versions of Opera (circa 7.11 on Windows) were vulnerable to one additional char 173 (the soft hypen control char). But the null char %00 is much more useful and helped me bypass certain real world filters with a variation on this example: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] breaks up cross site scripting vector. Here is a little known XSS attack vector using null characters. You can actually break up the HTML itself using the same nulls as shown above. I‘ve seen this vector bypass some of the most restrictive XSS filters to date: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] before the JavaScript in images for XSS (this is useful if the pattern match doesn‘t take into account spaces in the word "javascript:" -which is correct since that won‘t render- and makes the false assumption that you can‘t have a space between the quote and the "javascript:" keyword. The actual reality is you can have any char from 1-32 in decimal): Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] XSS. While I was reading the Firefox HTML parser I found that it assumes a non-alpha-non-digit is not valid after an HTML keyword and therefor considers it to be a whitespace or non-valid token after an HTML tag. The problem is that some XSS filters assume that the tag they are looking for is broken up by whitespace. For example "<SCRIPT\s" != "<SCRIPT/XSS\s": Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] XSS. yawnmoth brought my attention to this vector, based on the same idea as above, however, I expanded on it, using my fuzzer. The Gecko rendering engine allows for any character other than letters, numbers or encapsulation chars (like quotes, angle brackets, etc...) between the event handler and the equals sign, making it easier to bypass cross site scripting blocks. Note that this does not apply to the grave accent char as seen here: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] . Submitted by Franz Sedlmaier, this XSS vector could defeat certain detection engines that work by first using matching pairs of open and close angle brackets and then by doing a comparison of the tag inside, instead of a more efficient algorythm likeBoyer-Moore that looks for entire string matches of the open angle bracket and associated tag (post de-obfuscation, of course). The double slash comments out the ending extraneous bracket to supress a JavaScript error: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] . In Firefox and Netscape 8.1 in the Gecko rendering engine mode you don‘t actually need the "></SCRIPT>" portion of this Cross Site Scripting vector. Firefox assumes it‘s safe to close the HTML tag and add closing tags for you. How thoughtful! Unlike the next one, which doesn‘t effect Firefox, this does not require any additional HTML below it. You can add quotes if you need to, but they‘re not needed generally, although beware, I have no idea what the HTML will end up looking like once this is injected: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] . This particular variant was submitted by?ukasz Pilorz and was based partially off of Ozh‘s protocol resolution bypass below. This cross site scripting example works in IE, Netscape in IE rendering mode and Opera if you add in a </SCRIPT> tag at the end. However, this is especially useful where space is an issue, and of course, the shorter your domain, the better. The ".j" is valid, regardless of the MIME type because the browser knows it in context of a SCRIPT tag. Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] HTML/JavaScript XSS vector. Unlike Firefox the IE rendering engine doesn‘t add extra data to your page, but it does allow the javascript: directive in images. This is useful as a vector because it doesn‘t require a close angle bracket. This assumes there is any HTML tag below where you are injecting this cross site scripting vector. Even though there is no close ">" tag the tags below it will close it. A note: this does mess up the HTML, depending on what HTML is beneath it. It gets aroundthe following NIDS regex: /((\%3D)|(=))[^\n]*((\%3C)|<)[^\n]+((\%3E)|>)/ because it doesn‘t require the end ">". As a side note, this was also affective against a real world XSS filter I came across using an open ended <IFRAME tag instead of an <IMG tag: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] angle brackets. This is an odd one thatSteven Christey brought to my attention. At first I misclassified this as the same XSS vector as above but it‘s surprisingly different. Using an open angle bracket at the end of the vector instead of a close angle bracket causes different behavior in Netscape Gecko rendering. Without it, Firefox will work but Netscape won‘t: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] : Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] . When the application is written to output some user information inside of a JavaScript like the following: <SCRIPT>var a="$ENV{QUERY_STRING}";</SCRIPT> and you want to inject your own JavaScript into it but the server side application escapes certain quotes you can circumvent that by escaping their escape character. When this is gets injected it will read <SCRIPT>var a="\\";alert(‘XSS‘);//";</SCRIPT> which ends up un-escaping the double quote and causing the Cross Site Scripting vector to fire. TheXSS locator uses this method.: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] . This is a simple XSS vector that closes <TITLE> tags, which can encapsulate the malicious cross site scripting attack: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] : Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] : Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] (I like this method because it doesn‘t require using any variants of "javascript:" or "<SCRIPT..." to accomplish the XSS attack).Dan Crowley additionally noted that you can put a space before the equals sign ("onload=" != "onload ="): Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] that can be used in similar XSS attacks to the one above (this is the most comprehensive list on the net, at the time of this writing). Please note I have excluded browser support from this section because each one may have different results in different browsers. Thanks toRene Ledosquet for the HTML+TIME updates: : Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] : Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] : Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] (works in Netscape 4.x): Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] [NS4] (also only works in Netscape 4.x) Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] [NS4] : Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] (using something as simple as a remote style sheet you can include your XSS as the style parameter can be redefined using an embedded expression.) This only works in IE and Netscape 8.1+ in IE rendering engine mode. Notice that there is nothing on the page to show that there is included JavaScript. Note: With all of these remote style sheet examples they use the body tag, so it won‘t work unless there is some content on the page other than the vector itself, so you‘ll need to add a single letter to the page to make it work if it‘s an otherwise blank page: Browser support: [IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] (this works the same as above, but uses a <STYLE> tag instead of a <LINK> tag). A slight variation on this vector was used tohack Google Desktop. As a side note, you can remove the end </STYLE> tag if there is HTML immediately after the vector to close it. This is useful if you cannot have either an equals sign or a slash in your cross site scripting attack, which has come up at least once in the real world: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] . This only works in Opera but is fairly tricky. According toRFC2616 setting a link header is not part of the HTTP1.1 spec, however some browsers still allow it (like Firefox and Opera). The trick here is that I am setting a header (which is basically no different than in the HTTP header saying Link: <http://ha.ckers.org/xss.css>; REL=stylesheet) and the remote style sheet with my cross site scripting vector is running the JavaScript, which is not supported in FireFox: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] . This only works in Gecko rendering engines and works by binding an XUL file to the parent page. I think the irony here is that Netscape assumes that Gecko is safer and therefor is vulnerable to this for the vast majority of sites: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] . This is a little different than the above two cross site scripting vectors because it uses an .htc file which must be on the same server as the XSS vector. The example file works by pulling in the JavaScript and running it as part of the style attribute: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] . Fairly esoteric issue dealing with embedding images for bulleted lists. This will only work in the IE rendering engine because of the JavaScript directive. Not a particularly useful cross site scripting vector: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] in an image: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] (older versions of Netscape only): Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] [NS4] (older versions of Netscape only): Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] [NS4] encoding (found byKurt Huwig). This uses malformed ASCII encoding with 7 bits instead of 8. This XSS may bypass many content filters but only works if the host transmits in US-ASCII encoding, or if you set the encoding yourself. This is more useful against web application firewall cross site scripting evasion than it is server side filter evasion. Apache Tomcat is the only known server that transmits in US-ASCII encoding: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] [NS4] (the odd thing about meta refresh is that it doesn‘t send a referrer in the header - so it can be used for certain types of attacks where you need to get rid of referring URLs): Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] URL scheme. This is nice because it also doesn‘t have anything visibly that has the word SCRIPT or the JavaScript directive in it, because it utilizes base64 encoding. Please seeRFC 2397 for more details or gohere orhere to encode your own. You can also use theXSS calculator below if you just want to encode raw HTML or JavaScript as it has a Base64 encoding method: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] . If the target website attempts to see if the URL contains "http://" at the beginning you can evade it with the following technique (Submitted byMoritz Naumann): Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] (if iframes are allowed there are a lot of other XSS problems as well): Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] (frames have the same sorts of XSS problems as iframes): Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] (who would have thought tables were XSS targets... except me, of course): Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] (just like above, TD‘s are vulnerable to BACKGROUNDs containing JavaScript XSS vectors): Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] : Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] exploit (this has been modified slightly to obfuscate the url parameter). The original vulnerability was found byRenaud Lifchitz as a vulnerability in Hotmail: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] . I built a quick XSS fuzzer to detect any erroneous characters that are allowed after the open parenthesis but before the JavaScript directive in IE and Netscape 8.1 in secure site mode. These are in decimal but you can include hex and add padding of course. (Any of the following chars can be used: 1-32, 34, 39, 160, 8192-8.13, 12288, 65279): Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] - a variant of this was effective against a real world cross site scripting filter using a newline between the colon and "expression": Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] tags with broken up JavaScript for XSS (this XSS at times sends IE into an infinite loop of alerts): Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] to break up expression (Thanks toRoman Ivanov for this one): Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] (IE6.0 and Netscape 8.1+ in IE rendering engine mode don‘t really care if the HTML tag you build exists or not, as long as it starts with an open angle bracket and a letter): Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] (this is really a hybrid of the above XSS vectors, but it really does show how hard STYLE tags can be to parse apart, like above this can send IE into a loop): Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] (Older versions of Netscape only): Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] [NS4] : Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] : Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] block (only works in IE5.0 and later and Netscape 8.1 in IE rendering engine mode). Some websites consider anything inside a comment block to be safe and therefore does not need to be removed, which allows our Cross Site Scripting vector. Or the system could add comment tags around something to attempt to render it harmless. As we can see, that probably wouldn‘t do the job: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] tag. Works in IE and Netscape 8.1 in safe mode. You need the // to comment out the next characters so you won‘t get a JavaScript error and your XSS tag will render. Also, this relies on the fact that the website uses dynamically placed images like "images/image.jpg" rather than full paths. If the path includes a leading forward slash like "/images/image.jpg" you can remove one slash from this vector (as long as there are two to begin the comment this will work): Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] tag (if they allow objects, you can also inject virus payloads to infect the users, etc. and same with the APPLET tag). The linked file is actually an HTML file that can contain your XSS: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] you can embed XSS directly (this is unverified so no browser support is added): you can embed a Flash movie that contains XSS.Click here for a demo. If you add the attributes allowScriptAccess="never" and allownetworking="internal" it can mitigate this risk (thank you to Jonathan Vanasco for the info).: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] inside flash can obfuscate your XSS vector: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] . The htc file must be located on the same server as your XSS vector: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] with CDATA obfuscation (this XSS attack works only in IE and Netscape 8.1 in IE rendering engine mode) - vector found bySec Consult while auditing Yahoo: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] (this is another take on the same exploit that doesn‘t use CDATA fields, but rather uses comments to break up the javascript directive): Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] that is generated using an XML data island. This is the same as above but instead referrs to a locally hosted (must be on the same server) XML file that contains your cross site scripting vector. You can see the resulthere: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] . This is how . This only works in Internet Explorer and Netscape 8.1 in IE rendering engine mode and remember that you need to be between HTML and BODY tags for this to work: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] file to an image as an XSS vector: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] (Server Side Includes) requires SSI to be installed on the server to use this XSS vector. I probably don‘t need to mention this, but if you can run commands on the server there are no doubt much more serious issues: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] - requires PHP to be installed on the server to use this XSS vector. Again, if you can run any scripts remotely like this, there are probably much more dire issues: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] commands - this works when the webpage where this is injected (like a web-board) is behind password protection and that password protection works with other commands on the same domain. This can be used to delete users, add users (if the user who visits the page is an administrator), send credentials elsewhere, etc.... This is one of the lesser used but more useful XSS vectors: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] - this is more scary because there are absolutely no identifiers that make it look suspicious other than it is not hosted on your own domain. The vector uses a 302 or 304 (others work too) to redirect the image back to a command. So a normal <IMG SRC="http://badguy.com/a.jpg"> could actually be an attack vector to run commands as the user who views the image link. Here is the .htaccess (under Apache) line to accomplish the vector (thanks to Timo for part of this): Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] - admittidly this is pretty obscure but I have seen a few examples where <META is allowed and you can use it to overwrite cookies. There are other examples of sites where instead of fetching the username from a database it is stored inside of a cookie to be displayed only to the user who visits the page. With these two scenarios combined you can modify the victim‘s cookie which will be displayed back to them as JavaScript (you can also use this to log people out or change their user states, get them to log in as you, etc...): Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] encoding - if the page that the XSS resides on doesn‘t provide a page charset header, or any browser that is set to UTF-7 encoding can be exploited with the following (Thanks toRoman Ivanov for this one). Clickhere for an example (you don‘t need the charset statement if the user‘s browser is set to auto-detect and there is no overriding content-types on the page in Internet Explorer and Netscape 8.1 in IE rendering engine mode). This does not work in any modern browser without changing the encoding type which is why it is marked as completely unsupported.Watchfire found this hole in Google‘s custom 404 script.: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] XSS using HTML quote encapsulation: This was tested in IE, your mileage may vary. For performing XSS on sites that allow "<SCRIPT>" but don‘t allow "<SCRIPT SRC..." by way of a regex filter "/<script[^>]+src/i": Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] For performing XSS on sites that allow "<SCRIPT>" but don‘t allow "<script src..." by way of a regex filter "/<script((\s+\w+(\s*=\s*(?:"(.)*?"|‘(.)*?‘|[^‘">\s]+))?)+\s*|\s*)src/i" (this is an important one, because I‘ve seen this regex in the wild): Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] Another XSS to evade the same filter, "/<script((\s+\w+(\s*=\s*(?:"(.)*?"|‘(.)*?‘|[^‘">\s]+))?)+\s*|\s*)src/i": Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] Yet another XSS to evade the same filter, "/<script((\s+\w+(\s*=\s*(?:"(.)*?"|‘(.)*?‘|[^‘">\s]+))?)+\s*|\s*)src/i". I know I said I wasn‘t goint to discuss mitigation techniques but the only thing I‘ve seen work for this XSS example if you still want to allow <SCRIPT> tags but not remote script is a state machine (and of course there are other ways to get around this if they allow <SCRIPT> tags): Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] And one last XSS attack to evade, "/<script((\s+\w+(\s*=\s*(?:"(.)*?"|‘(.)*?‘|[^‘">\s]+))?)+\s*|\s*)src/i" using grave accents (again, doesn‘t work in Firefox): Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] Here‘s an XSS example that bets on the fact that the regex won‘t catch a matching pair of quotes but will rather find any quotes to terminate a parameter string improperly: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] This XSS still worries me, as it would be nearly impossible to stop this without blocking all active content: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] URL string evasion (assuming "http://www.google.com/" is programmatically disallowed): IP verses hostname: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] URL encoding: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] Dword encoding (Note: there are other of variations of Dword encoding - see theIP Obfuscation calculator below for more details): Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] Hex encoding (the total size of each number allowed is somewhere in the neighborhood of 240 total characters as you can see on the second digit, and since the hex number is between 0 and F the leading zero on the third hex quotet is not required): Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] Octal encoding (again padding is allowed, although you must keep it above 4 total characters per class - as in class A, class B, etc...): Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] Mixed encoding (let‘s mix and match base encoding and throw in some tabs and newlines - why browsers allow this, I‘ll never know). The tabs and newlines only work if this is encapsulated with quotes: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] Protocol resolution bypass (// translates to http:// which saves a few more bytes). This is really handy when space is an issue too (two less characters can go a long way) and can easily bypass regex like "(ht|f)tp(s)?://" (thanks toOzh for part of this one). You can also change the "//" to "\\". You do need to keep the slashes in place, however, otherwise this will be interpreted as a relative path URL. Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] Google "feeling lucky" part 1. Firefox uses Google‘s "feeling lucky" function to redirect the user to any keywords you type in. So if your exploitable page is the top for some random keyword (as you see here) you can use that feature against any Firefox user. This uses Firefox‘s "keyword:" protocol. You can concatinate several keywords by using something like the following "keyword:XSS+RSnake" for instance. Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] Google "feeling lucky" part 2. This uses a very tiny trick that appears to work Firefox only, because if it‘s implementation of the "feeling lucky" function. Unlike the next one this does not work in Opera because Opera believes that this is the old HTTP Basic Auth phishing attack, which it is not. It‘s simply a malformed URL. If you click okay on the dialogue it will work, but as a result of the erroneous dialogue box I am saying that this is not supported in Opera: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] Google "feeling lucky" part 3. This uses a malformed URL that appears to work in Firefox and Opera only, because if their implementation of the "feeling lucky" function. Like all of the above it requires that you are #1 in Google for the keyword in question (in this case "google"): Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] Removing cnames (when combined with the above URL, removing "www." will save an additional 4 bytes for a total byte savings of 9 for servers that have this set up properly): Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] Extra dot for absolute DNS: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] JavaScript link location: Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] Content replace as attack vector (assuming "http://www.google.com/" is programmatically replaced with nothing). I actually used a similar attack vector against a several seperate real world XSS filters by using the conversion filter itself (here is an example) to help create the attack vector (IE: "java	script:" was converted into "java script:", which renders in IE, Netscape 8.1+ in secure site mode and Opera): Browser support: [IE7.0|IE6.0|NS8.1-IE] [NS8.1-G|FF1.5] [O8.54] Character Encoding: All the possible combinations of the character "<" in HTML and JavaScript (in UTF-8). Most of these won‘t render out of the box, but many of them can get rendered in certain circumstances as seen above (standards are great, aren‘t they?): ASCII Text: Hex Value: URL: HTML (with semicolons): Decimal Value: HTML (without semicolons): Base64 Value Base64: </form> IP Address: : dword level Dword Address: Hex Address: Octal Address: </form> Browser support reference table: IE7.0 Vector works in Internet Explorer 7.0. Most recently tested with Internet Explorer 7.0.5700.6 RC1, Windows XP Professional SP2. IE6.0 Vector works in Internet Explorer. Most recently tested with Internet Explorer 6.0.28.1.1106CO, SP2 on Windows 2000. NS8.1-IE Vector works in Netscape 8.1+ in IE rendering engine mode. Most recently tested with Netscape 8.1 on Windows XP Professional. This used to be called trusted mode, but Netscape has changed it‘s security model away from the trusted/untrusted model and has opted towards Gecko as a default and IE as an option. NS8.1-G Vector works in Netscape 8.1+ in the Gecko rendering engine mode. Most recently tested with Netscape 8.1 on Windows XP Professional FF1.5 Vector works in Mozilla‘s Gecko rendering engine, used by Firefox. Most recently tested with Firefox 1.5.0.4 on Windows XP Professional. O8.54 Vector works in Opera. Most recently tested with Opera 8.54, Build 7722 on Windows XP Professional NS4 Vector works in older versions of Netscape 4.0 - untested. Note: if a vector is not marked it either does not work or it is untested.</div> <div class="list-group"> <a href="/article/72984" class="list-group-item">XSS (Cross Site Scripting) Cheat Sheet</a> <a href="/article/282376" class="list-group-item">Kallahar‘s Place: PHP XSS (cross site scripting) filter function</a> <a href="/article/835713" class="list-group-item">Cross-Site Scripting</a> <a href="/article/12046" class="list-group-item">Python Cheat Sheet</a> <a href="/article/2016078" class="list-group-item">Watir : Cheat Sheet</a> <a href="/article/7181" class="list-group-item">CSS Cheat Sheet - CSS - ILoveJackDaniels.com</a> <a href="/article/2741279" class="list-group-item">Cheat Sheet – Architecture Meta Frame (AMF)</a> <a href="/article/20715" class="list-group-item">Ruby on Rails Cheat Sheet - Ruby On Rails - ILoveJackDaniels.com</a> <a href="/article/28431" class="list-group-item">Google Guide Quick Reference: Google Advanced Operators (Cheat Sheet)</a> <a href="/article/363669" class="list-group-item">SEOmoz | The Web Developer's SEO Cheat Sheet</a> <a href="/article/260338" class="list-group-item">Cross</a> <a href="/article/14764" class="list-group-item">Cross-Browser XMLHttpRequest - Web Site Design - Andrew Gregory‘s Web Pages</a> <a href="/article/84912" class="list-group-item">XSS攻击</a> <a href="/article/260572" class="list-group-item">MatrixPedia: XSS</a> <a href="/article/434323" class="list-group-item">XSS攻击</a> <a href="/article/723558" class="list-group-item">Cross Marriage</a> <a href="/article/2806665" class="list-group-item">cross车型</a> <a href="/article/100301" class="list-group-item">XSS 0DAY</a> <a href="/article/999227" class="list-group-item">XSS 0DAY</a> <a href="/article/1023341" class="list-group-item">Site Map</a> <a href="/article/464595" class="list-group-item">Windows Scripting - 簡易資料備份</a> <a href="/article/589080" class="list-group-item">Advanced Bash-Scripting Guide</a> <a href="/article/2768588" class="list-group-item">Scripting Xilinx? ISE? using Tcl</a> <a href="/article/14766" class="list-group-item">Cross-Browser XMLHttpRequest</a> </div> </div> </div> </div> </div> </div> <footer id="footer" class="footer hidden-print"> <div class="container"> <div class="panel panel-default"> <div class="panel-heading">相关问题</div> <div class="panel-body"> <a class="btn btn-default" href="/article/1236608" title="经典PS实例教程10000例,打造PS高手/适合各个阶段 - 网络/软件技巧&答疑 - 电...">经典PS实例教程10000例,打造PS高手/适合各个阶段 - 网络/软件技巧&答疑 - 电...</a> <a class="btn btn-default" href="/article/1236609" title="千寻奇招：散户股票">千寻奇招：散户股票</a> <a class="btn btn-default" href="/article/1236610" title="企业股权转让的资料整理">企业股权转让的资料整理</a> <a class="btn btn-default" href="/article/1236611" title="丁远博士的简单投资策略">丁远博士的简单投资策略</a> <a class="btn btn-default" href="/article/1236612" title="想奶奶">想奶奶</a> <a class="btn btn-default" href="/article/1236613" title="手背、手掌穴位图-漆树家园-搜狐博客,">手背、手掌穴位图-漆树家园-搜狐博客,</a> <a class="btn btn-default" href="/article/1236614" title="1871年大清总理衙门的大臣清晰照--董恂">1871年大清总理衙门的大臣清晰照--董恂</a> <a class="btn btn-default" href="/article/1236615" title="股权转让协议">股权转让协议</a> <a class="btn btn-default" href="/article/1236616" title="“前腐后继”仨厅长咋比拼廉政雷语？－廉路心语－廉路小语心迹留痕－强国博客－人民网">“前腐后继”仨厅长咋比拼廉政雷语？－廉路心语－廉路小语心迹留痕－强国博客－人民网</a> <a class="btn btn-default" href="/article/1236617" title="心理学解读郁闷">心理学解读郁闷</a> <a class="btn btn-default" href="/article/1236618" title="坏消息是投资者最好的朋友">坏消息是投资者最好的朋友</a> <a class="btn btn-default" href="/article/1236619" title="机构调研规模空前新疆股巅峰对决投资秘笈曝光">机构调研规模空前新疆股巅峰对决投资秘笈曝光</a> <a class="btn btn-default" href="/article/1236620" title="两年股价就涨了十几倍五种选股标准最新思路">两年股价就涨了十几倍五种选股标准最新思路</a> <a class="btn btn-default" href="/article/1236621" title="令男人拥有更强更阳刚的五个穴位『图文』,">令男人拥有更强更阳刚的五个穴位『图文』,</a> <a class="btn btn-default" href="/article/1236622" title="很有用，办公室生存的十大护身符">很有用，办公室生存的十大护身符</a> <a class="btn btn-default" href="/article/1236623" title="只需你十分钟却可以让你和你的父母都至少多活十年-{～北大齐教授健康讲座笔录">只需你十分钟却可以让你和你的父母都至少多活十年-{～北大齐教授健康讲座笔录</a> <a class="btn btn-default" href="/article/1236624" title="期货经验谈(1)前言">期货经验谈(1)前言</a> <a class="btn btn-default" href="/article/1236625" title="坐姿抬臀功瑜伽瘦身五分钟">坐姿抬臀功瑜伽瘦身五分钟</a> <a class="btn btn-default" href="/article/1236626" title="Consuelo Mack WealthTrack - Transcripts">Consuelo Mack WealthTrack - Transcripts</a> <a class="btn btn-default" href="/article/1236627" title="1信用卡知识大全">1信用卡知识大全</a> <a class="btn btn-default" href="/article/1236628" title="职场中的无形资产">职场中的无形资产</a> <a class="btn btn-default" href="/article/1236629" title="【土单验方】安全实用的特效秘方100条">【土单验方】安全实用的特效秘方100条</a> <a class="btn btn-default" href="/article/1236630" title="【土单验方】止痛10大妙招">【土单验方】止痛10大妙招</a> <a class="btn btn-default" href="/article/1236631" title="个人理财的基本法则和技巧">个人理财的基本法则和技巧</a> <a class="btn btn-default" href="/article/1236632" title="强身健体，每天必做之11功课">强身健体，每天必做之11功课</a> <a class="btn btn-default" href="/article/1236633" title="《国家地理》杂志2008年最佳摄影作品［38P］">《国家地理》杂志2008年最佳摄影作品［38P］</a> <a class="btn btn-default" href="/article/1236634" title="民间相士秘籍口诀">民间相士秘籍口诀</a> <a class="btn btn-default" href="/article/1236635" title="八段经典演讲节选（中英文对照）*^*-萍萍的空间-考拉网">八段经典演讲节选（中英文对照）*^*-萍萍的空间-考拉网</a> <a class="btn btn-default" href="/article/1236636" title="凤凰古城游（去不去的都看看）">凤凰古城游（去不去的都看看）</a> <a class="btn btn-default" href="/article/1236637" title="温州一人大副主任致女学生怀孕女子欲跳楼事发">温州一人大副主任致女学生怀孕女子欲跳楼事发</a> <a class="btn btn-default" href="/article/1236638" title="董兆致">董兆致</a> </div> </div></div> <div class="copy-right"> 神马文学网，客观、专业、权威的知识性互动百科全书。</div> </footer> </body> </html>