How severe is CVE-2026-45075?

No CVSS score has been assigned to CVE-2026-45075 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by CVE-2026-45075?

CVE-2026-45075 affects the following packages: symfony/http-kernel (Packagist), symfony/http-kernel (Packagist), symfony/security-http (Packagist), symfony/security-http (Packagist), symfony/symfony (Packagist), symfony/symfony (Packagist). Ecosystems affected: Packagist.

How do I fix CVE-2026-45075?

Update symfony/http-kernel to 7.4.12 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-45075 is resolved across your whole dependency graph.

How do I detect CVE-2026-45075 in my Packagist dependencies?

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.

How do I mitigate CVE-2026-45075 if there is no patch (or I can't update yet)?

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.

Is CVE-2026-45075 actively exploited in the wild?

No public exploit code has been indexed for CVE-2026-45075 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2026-45075?

CVE-2026-45075 has an EPSS (Exploit Prediction Scoring System) score of 0.4%, placing it in the 35th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2026-45075?

CVE-2026-45075 is classified as CWE-863 (CWE-863). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2026-45075 published, and has it been updated?

CVE-2026-45075 was published on July 14, 2026 and was last updated on August 12, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐘 Packagist

Not in CISA KEV

CVE-2026-45075 — http-kernel

Fix: symfony/symfony@fa8d5c6

CVE-2026-45075 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.

Symfony: HEAD Request Bypasses methods: ['GET'] Filter in #[IsGranted] / #[IsSignatureValid] / #[IsCsrfTokenValid]

Also known asGHSA-6439-2f28-8p8q

Published

Jul 14, 2026

Updated

Aug 12, 2026

Affected

6 pkgs

Patched

6 / 6

Exploits

None indexed

Exploitation data as of Oct 8, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

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 CVE-2026-45075.

EPSS Exploitation Probability

via FIRST.org ↗

0.4%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs35th percentile — riskier than 35% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

Real-World Exposure

6 pkgs affected

🐘symfony/http-kernel🐘symfony/http-kernel🐘symfony/security-http🐘symfony/security-http🐘symfony/symfony🐘symfony/symfony

Real-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

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

6 total 6 fixed

Ecosystem	Package	Vulnerable range	Fix
🐘Packagist	`symfony/http-kernel`	≥ 7.4.0&&< 7.4.12	7.4.12`composer require symfony/http-kernel:^7.4.12`
🐘Packagist	`symfony/http-kernel`	≥ 8.0.0&&< 8.0.12	8.0.12`composer require symfony/http-kernel:^8.0.12`
🐘Packagist	`symfony/security-http`	≥ 7.4.0&&< 7.4.12	7.4.12`composer require symfony/security-http:^7.4.12`
🐘Packagist	`symfony/security-http`	≥ 8.0.0&&< 8.0.12	8.0.12`composer require symfony/security-http:^8.0.12`
🐘Packagist	`symfony/symfony`	≥ 7.4.0&&< 7.4.12	7.4.12`composer require symfony/symfony:^7.4.12`
🐘Packagist	`symfony/symfony`	≥ 8.0.0&&< 8.0.12	8.0.12`composer require symfony/symfony:^8.0.12`

Affected Products

1 product · 2 configurations

Application

symfonysensiolabs

≥ 8.0.0 && < 8.0.12

range

Detection & mitigation playbook

Open-source dependency

Detect
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 CVE-2026-45075 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

### 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 s