Symfony's HEAD Request Bypasses methods: ['GET'] Filter in #[IsGranted] / #[IsSignatureValid] / #[IsCsrfTokenValid]GHSA-6439-2f28-8p8q
Fix: symfony/symfony@fa8d5c6GHSA-6439-2f28-8p8q is a CWE-863 vulnerability in symfony/http-kernel. A fix is available for symfony/http-kernel — see the affected versions and patch details below.
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for GHSA-6439-2f28-8p8q.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
Real-World Exposure
symfony/http-kernel🐘symfony/http-kernel🐘symfony/security-http🐘symfony/security-http🐘symfony/symfony🐘symfony/symfonyReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.
Description
Description
Symfony's #[IsGranted('...')], #[IsSignatureValid], and #[IsCsrfTokenValid(...)] attributes allow you to define a methods: [...] argument to only enforce these checks for the listed HTTP methods and skip them otherwise. E.g. an attribute defining methods: ['GET'] would be ignored for a HEAD request.
On the other hand, Symfony's router (and HTTP semantics generally) serves HEAD requests using the GET handler. Therefore, a controller protected by e.g. #[IsGranted('ROLE_ADMIN', methods: ['GET'])] can be reached via HEAD with the authorization check silently skipped.
Even if the HEAD request won't get any response content, response headers leak (Content-Length, Location, custom headers). Also, the controller still executes and any side effects (DB writes, state changes) occur.
Resolution
When adding GET in the methods option of these attributes, Symfony now also include the HEAD method automatically.
The patch for this issue is available here for branch 7.4.
Credits
Symfony would like to thank Claude Mythos Preview (via Project Glasswing) for reporting the issue and Alexandre Daubois for fixing it.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | symfony/http-kernel | ≥ 7.4.0&&< 7.4.12 | 7.4.12composer require symfony/http-kernel:^7.4.12 |
| 🐘Packagist | symfony/http-kernel | ≥ 8.0.0&&< 8.0.12 | 8.0.12composer require symfony/http-kernel:^8.0.12 |
| 🐘Packagist | symfony/security-http | ≥ 7.4.0&&< 7.4.12 | 7.4.12composer require symfony/security-http:^7.4.12 |
| 🐘Packagist | symfony/security-http | ≥ 8.0.0&&< 8.0.12 | 8.0.12composer require symfony/security-http:^8.0.12 |
| 🐘Packagist | symfony/symfony | ≥ 7.4.0&&< 7.4.12 | 7.4.12composer require symfony/symfony:^7.4.12 |
| 🐘Packagist | symfony/symfony | ≥ 8.0.0&&< 8.0.12 | 8.0.12composer require symfony/symfony:^8.0.12 |
Affected Products
symfonysensiolabsDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for symfony/http-kernel, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update symfony/http-kernel to 7.4.12 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-6439-2f28-8p8q is resolved across your whole dependency graph.
Workarounds
Put an independent control in front of the weakness: restrict the affected endpoint or interface to trusted networks, require an additional authentication factor or proxy-level check, and invalidate existing sessions and credentials in case the flaw has already been used.
Frequently Asked Questions
Is GHSA-6439-2f28-8p8q in your dependencies?
Find it across Packagist, including transitive dependencies.