Description
The web application does not, or cannot, sufficiently verify whether a request was intentionally provided by the user who sent the request, which could have originated from an unauthorized actor.
CSRF Attacks Guide
Read our in-depth guide on exploiting and mitigating this weakness
Potential Impact
Confidentiality, Integrity, Availability, Non-Repudiation, Access Control
Gain Privileges or Assume Identity, Bypass Protection Mechanism, Read Application Data, Modify Application Data, DoS: Crash, Exit, or Restart
Demonstrative Examples
<form action="/url/profile.php" method="post"><input type="text" name="firstname"/><input type="text" name="lastname"/><br/><input type="text" name="email"/><input type="submit" name="submit" value="Update"/></form>// initiate the session in order to validate sessions
session_start();
//if the session is registered to a valid user then allow update
if (! session_is_registered("username")) {
echo "invalid session detected!";
// Redirect user to login page
[...]
exit;
}
// The user session is valid, so process the request
// and update the information
update_profile();
function update_profile {
// read in the data from $POST and send an update
// to the database
SendUpdateToDatabase($_SESSION['username'], $_POST['email']);[...]echo "Your profile has been successfully updated.";
}<SCRIPT>function SendAttack () {form.email = "[email protected]";
// send to profile.php
form.submit();}</SCRIPT>
<BODY onload="javascript:SendAttack();">
<form action="http://victim.example.com/profile.php" id="form" method="post"><input type="hidden" name="firstname" value="Funny"><input type="hidden" name="lastname" value="Joke"><br/><input type="hidden" name="email"></form>Mitigations & Prevention
Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid [REF-1482]. For example, use anti-CSRF packages such as the OWASP CSRFGuard. [REF-330] Another example is the ESAPI Session Management control, which includes a component for CSRF. [REF-45]
Ensure that the application is free of cross-site scripting issues (CWE-79), because most CSRF defenses can be bypassed using attacker-controlled script.
Generate a unique nonce for each form, place the nonce into the form, and verify the nonce upon receipt of the form. Be sure that the nonce is not predictable (CWE-330). [REF-332]
Identify especially dangerous operations. When the user performs a dangerous operation, send a separate confirmation request to ensure that the user intended to perform that operation.
Use the "double-submitted cookie" method as described by Felten and Zeller: When a user visits a site, the site should generate a pseudorandom value and set it as a cookie on the user's machine. The site should require every form submission to include this value as a form value and also as a cookie value. When a POST request is sent to the site, the request should only be considered valid if the form value and the cookie value are the same. Because of the
Do not use the GET method for any request that triggers a state change.
Check the HTTP Referer header to see if the request originated from an expected page. This could break legitimate functionality, because users or proxies may have disabled sending the Referer for privacy reasons.
Detection Methods
- Manual Analysis High — This weakness can be detected using tools and techniques that require manual (human) analysis, such as penetration testing, threat modeling, and interactive tools that allow the tester to record and modify an active session. Specifically, manual analysis can be useful for finding
- Automated Static Analysis Limited — CSRF is currently difficult to detect reliably using automated techniques. This is because each application has its own implicit security policy that dictates which requests can be influenced by an outsider and automatically performed on behalf of a user, versus which requests require strong confide
- Automated Static Analysis - Binary or Bytecode SOAR Partial — According to SOAR [REF-1479], the following detection techniques may be useful:
- Manual Static Analysis - Binary or Bytecode SOAR Partial — According to SOAR [REF-1479], the following detection techniques may be useful:
- Dynamic Analysis with Automated Results Interpretation High — According to SOAR [REF-1479], the following detection techniques may be useful:
- Dynamic Analysis with Manual Results Interpretation High — According to SOAR [REF-1479], the following detection techniques may be useful:
Real-World CVE Examples
| CVE ID | Description |
|---|---|
| CVE-2004-1703 | Add user accounts via a URL in an img tag |
| CVE-2004-1995 | Add user accounts via a URL in an img tag |
| CVE-2004-1967 | Arbitrary code execution by specifying the code in a crafted img tag or URL |
| CVE-2004-1842 | Gain administrative privileges via a URL in an img tag |
| CVE-2005-1947 | Delete a victim's information via a URL or an img tag |
| CVE-2005-2059 | Change another user's settings via a URL or an img tag |
| CVE-2005-1674 | Perform actions as administrator via a URL or an img tag |
| CVE-2009-3520 | modify password for the administrator |
| CVE-2009-3022 | CMS allows modification of configuration via CSRF attack against the administrator |
| CVE-2009-3759 | web interface allows password changes or stopping a virtual machine via CSRF |
Related Weaknesses
Taxonomy Mappings
- PLOVER: — Cross-Site Request Forgery (CSRF)
- OWASP Top Ten 2007: A5 — Cross Site Request Forgery (CSRF)
- WASC: 9 — Cross-site Request Forgery
Frequently Asked Questions
What is CWE-352?
CWE-352 (Cross-Site Request Forgery (CSRF)) is a software weakness identified by MITRE's Common Weakness Enumeration. It is classified as a Compound-level weakness. The web application does not, or cannot, sufficiently verify whether a request was intentionally provided by the user who sent the request, which could have originated from an unauthorized actor.
How can CWE-352 be exploited?
Attackers can exploit CWE-352 (Cross-Site Request Forgery (CSRF)) to gain privileges or assume identity, bypass protection mechanism, read application data, modify application data, dos: crash, exit, or restart. This weakness is typically introduced during the Architecture and Design phase of software development.
How do I prevent CWE-352?
Key mitigations include: Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid [REF-1482]. For example, use anti-CSRF p
What is the severity of CWE-352?
CWE-352 is classified as a Compound-level weakness (Complex abstraction). It has been observed in 10 real-world CVEs.