GHSA-92x6-h2gr-8gxq CVE-2017-16653
Symfony CSRF Vulnerability
Medium
Packagist
- Severity
- 5.9 / 10
- Medium · CVSS 3.0
- Exploit chance (EPSS)
- 1.49%
- Chance of exploitation in the next 30 days. Higher than 74.03% of scored vulnerabilities.
- Known exploited
- No
- Not in CISA's catalog
- Weakness
- CWE-352 Cross-Site Request Forgery (CSRF)
- Fix
- Available
- 3 packages have a fixed version
Description
An issue was discovered in Symfony before 2.7.38, 2.8.31, 3.2.14, 3.3.13, 3.4-BETA5, and 4.0-BETA5. The current implementation of CSRF protection in Symfony (Version >=2) does not use different tokens for HTTP and HTTPS; therefore the token is subject to MITM attacks on HTTP and can then be used in an HTTPS context to do CSRF attacks.
Affected versions
Packagist
| Package | Vulnerable | Fixed in |
|---|---|---|
| symfony/security | >= 2.7.0, < 2.7.38 |
2.7.38 |
| symfony/security | >= 2.8.0, < 2.8.31 |
2.8.31 |
| symfony/security | >= 3.0.0, < 3.2.14 |
3.2.14 |
| symfony/security | >= 3.3.0, < 3.3.13 |
3.3.13 |
| symfony/security-csrf | >= 2.7.0, < 2.7.38 |
2.7.38 |
| symfony/security-csrf | >= 2.8.0, < 2.8.31 |
2.8.31 |
| symfony/security-csrf | >= 3.0.0, < 3.2.14 |
3.2.14 |
| symfony/security-csrf | >= 3.3.0, < 3.3.13 |
3.3.13 |
| symfony/symfony | >= 2.7.0, < 2.7.38 |
2.7.38 |
| symfony/symfony | >= 2.8.0, < 2.8.31 |
2.8.31 |
| symfony/symfony | >= 3.0.0, < 3.2.14 |
3.2.14 |
| symfony/symfony | >= 3.3.0, < 3.3.13 |
3.3.13 |
How to fix
Move to the fixed version or later with your package manager, update the lockfile, and run your tests. If the package only arrives through another dependency, upgrade that dependency first. If none of its releases pulls a fixed version yet, force the version with your package manager's override.
symfony/security Packagist → 2.7.38
- composer
composer require symfony/security:^2.7.38
symfony/security-csrf Packagist → 2.7.38
- composer
composer require symfony/security-csrf:^2.7.38
symfony/symfony Packagist → 2.7.38
- composer
composer require symfony/symfony:^2.7.38
Severity breakdown
CVSS 3.0 5.9
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
- Attack vector
- Network
- Attack complexity
- High
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- None
Weakness
CWE-352: Cross-Site Request Forgery (CSRF)
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 to prevent it
- Architecture and Design: 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]
- Implementation: Ensure that the application is free of cross-site scripting issues (CWE-79), because most CSRF defenses can be bypassed using attacker-controlled script.
- Architecture and Design: 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]
- Architecture and Design: 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.
- Architecture and Design: 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 same-origin policy, an attacker cannot read or modify the value stored in the cookie. To successfully submit a form on behalf of the user, the attacker would have to correctly guess the pseudorandom value. If the pseudorandom value is cryptographically strong, this will be prohibitively difficult. This technique requires Javascript, so it may not work for browsers that have Javascript disabled. [REF-331]
- Architecture and Design: Do not use the GET method for any request that triggers a state change.
- Implementation: 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.
References
Advisories
Packages
Other links
- github.com/symfony/symfony/pull/24992
- github.com/symfony/symfony/commit/b4dbdd7cd8732483d585eacff3428c16b07ad15e
- github.com/FriendsOfPHP/security-advisories/blob/master/symfony/security-csrf/C…
- github.com/FriendsOfPHP/security-advisories/blob/master/symfony/security/CVE-20…
- github.com/FriendsOfPHP/security-advisories/blob/master/symfony/symfony/CVE-201…
- symfony.com/blog/cve-2017-16653-csrf-protection-does-not-use-different-tokens-fo…
- symfony.com/cve-2017-16653
- debian.org/security/2018/dsa-4262
Timeline
- Published
- Last updated by the source
- Latest EPSS score
Related advisories
| Advisory | Severity | Why it's related |
|---|---|---|
| GHSA-2v3c-qxhr-7vpv Symfony: Unbounded Recursion in the YAML Inline Lexer Lets a Single Document Crash the Process | High | Also affects symfony/symfony |
| GHSA-r925-mgvr-h9cc Symfony: ReDoS in HeaderUtils::split() Reachable Through the Cache-Control Request Header | High | Also affects symfony/symfony |
| GHSA-h5x3-xfc9-m39h Symfony: UrlGenerator Dot-Segment Encoding Skips Every Other Chained `../` or `./` → Generated URL Collapses Off-Route Under RFC 3986 Normalization | Medium | Also affects symfony/symfony |
| GHSA-v3wm-qf9p-c549 Symfony: HtmlSanitizer URL Parser Deny Gates Underinclusive: Percent-Encoded BiDi Marks and Unicode Whitespace Bypass Visual-Spoofing Defense | Medium | Also affects symfony/symfony |
| GHSA-rrj9-5q2j-4gvr Symfony: Mailomat Mailer Webhook Parser Reads the HMAC Algorithm from the Request: Signature Algorithm Downgrade | Medium | Also affects symfony/symfony |
| GHSA-38cx-cq6f-5755 Symfony: IpUtils::PRIVATE_SUBNETS Omits IPv6 Transition Forms (6to4, NAT64, Teredo, IPv4-compatible): SSRF Bypass in NoPrivateNetworkHttpClient | High | Also affects symfony/symfony |
| GHSA-6h46-9jf5-q59x Symfony: Security Firewall Bypass via failure_forward Subrequest: Unauthenticated Access to access_control-Protected GET Routes | High | Also affects symfony/symfony |
| GHSA-x5qj-865h-mgvm Symfony: HtmlSanitizer UrlAttributeSanitizer Misses URL Attributes | Medium | Also affects symfony/symfony |
MergeHarbor checks every repository's dependencies against this database, ranks what matters by exploitability and reachability, routes it to the owning team and opens the fix pull request.
Check your repos with MergeHarbor