Your RSA-2048 keys break in 2030. Find every one of them before attackers do.
🐘 Packagist

CVE-2026-41129

CVE-2026-41129 is a security vulnerability in craftcms/cms. O3 Security confirms whether CVE-2026-41129 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.

Craft CMS has Server-Side Request Forgery (SSRF) with Asset Uploads Mutations

Also known asGHSA-3m9m-24vh-39wx
Published
Apr 21, 2026
Updated
Aug 4, 2026
Affected
2 pkgs
Patched
2 / 2
Exploits
None indexed

Blast Radius

2 pkgs affected
🐘craftcms/cms🐘craftcms/cms

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

Craft CMS is a content management system (CMS). Versions on the 4.x branch through 4.17.8 and the 5.x branch through 5.9.14 are vulnerable to Server-Side Request Forgery. The exploitation requires a few permissions to be enabled in the used GraphQL schema: "Edit assets in the <VolumeName> volume" and "Create assets in the <VolumeName> volume." Versions 4.17.9 and 5.9.15 patch the issue.

Affected Packages

2 total 2 fixed
EcosystemPackageVulnerable rangeFix
🐘Packagistcraftcms/cms5.0.0-RC1&&< 5.9.155.9.15
🐘Packagistcraftcms/cms4.0.0-RC1&&< 4.17.94.17.9

Detection & mitigation playbook

Open-source dependency
  1. Detect

    Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for craftcms/cms. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

  2. Fix

    Update craftcms/cms to 5.9.15 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-41129 is resolved across your whole dependency graph.

  3. Workarounds

    If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

  4. How O3 protects you

    O3 pinpoints whether CVE-2026-41129 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to CVE-2026-41129. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

Craft CMS is a content management system (CMS). Versions on the 4.x branch through 4.17.8 and the 5.x branch through 5.9.14 are vulnerable to Server-Side Request Forgery. The exploitation requires a few permissions to be enabled in the used GraphQL schema: "Edit assets in the <VolumeName> volume" and "Create assets in the <VolumeName> volume." Versions 4.17.9 and 5.9.15 patch the issue.
O3 Security · Impact-Aware SCA

Is CVE-2026-41129 in your dependencies?

O3 detects CVE-2026-41129 across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.