Your RSA-2048 keys break in 2030. Find every one of them before attackers do.
🐘 Packagist
Not in CISA KEV

GHSA-6mrr-q3pj-h53w — craftcms/cms

Fix: craftcms/cms@7f0ead8

GHSA-6mrr-q3pj-h53w is a Missing Authentication vulnerability in craftcms/cms. A fix is available for craftcms/cms — see the affected versions and patch details below.

Craft CMS: Unauthenticated Users Can Perform Restricted Project Config Sync Operations

Also known asCVE-2026-33159
Published
Mar 24, 2026
Updated
Mar 25, 2026
Affected
2 pkgs
Patched
2 / 2
Exploits
None indexed
Exploitation data as of Sep 18, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

Proof-of-concept exploit code exists

  • CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
  • CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.

Exploitation and automatability from CISA’s SSVC triage for GHSA-6mrr-q3pj-h53w.

EPSS Exploitation Probability

via FIRST.org ↗
0.3%probability of exploitation in next 30 days
Lower Risk0.00%
Lower risk than most CVEs24th percentile — riskier than 24% of all scored CVEsHighest risk

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Real-World Exposure

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

Summary

Guest users can access Config Sync updater index, obtain signed data, and execute state-changing Config Sync actions (regenerate-yaml, apply-yaml-changes) without authentication.

Details

ConfigSyncController extends BaseUpdaterController, and the base updater is anonymously accessible for control panel requests. index emits signed updater state (data), which can be reused by guests in subsequent requests.

Sensitive actions that are reachable via this method are actionApplyYamlChanges, actionRegenerateYaml, applyExternalChanges, and regenerateExternalConfig.

Reproduction steps

  1. Guest POST to:

    http POST /admin/actions/config-sync/index

  2. Extract data from returned JS state:

Craft.updater = ... setState({"data":"<signedData>", ...});
  1. Reuse data as a guest:
  POST /admin/actions/config-sync/regenerate-yaml
  data=<signedData>&<csrfParam>=<csrfToken>

or

  POST /admin/actions/config-sync/apply-yaml-changes
  data=<signedData>&<csrfParam>=<csrfToken>
  1. Observe completed response and state/file changes.

Impact

Unauthenticated users can execute project configuration sync operations that should be restricted to trusted admin/deployment contexts.

Depending on the pending YAML/config state, this can cause unauthorized config state transitions and a service integrity risk.

Resources

https://github.com/craftcms/cms/commit/7f0ead833f7

Affected Packages

2 total 2 fixed
EcosystemPackageVulnerable rangeFix
🐘Packagistcraftcms/cms≥ 5.0.0-RC1&&< 5.9.145.9.14composer require craftcms/cms:^5.9.14
🐘Packagistcraftcms/cms≥ 4.0.0-RC1&&< 4.17.84.17.8composer require craftcms/cms:^4.17.8

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, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

  2. Fix

    Update craftcms/cms to 5.9.14 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-6mrr-q3pj-h53w 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 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-6mrr-q3pj-h53w can be triaged on real exposure rather than presence alone.

Tailored to GHSA-6mrr-q3pj-h53w. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

### Summary Guest users can access Config Sync updater `index`, obtain signed `data`, and execute state-changing Config Sync actions (`regenerate-yaml`, `apply-yaml-changes`) without authentication. ### Details `ConfigSyncController` extends `BaseUpdaterController`, and the base updater is anonymously accessible for control panel requests. `index` emits signed updater state (`data`), which can be reused by guests in subsequent requests. Sensitive actions that are reachable via this method are `actionApplyYamlChanges`, `actionRegenerateYaml`, `applyExternalChanges`, and `regenerateExternal
O3 Security · Impact-Aware SCA

Is GHSA-6mrr-q3pj-h53w in your dependencies?

O3 Security finds GHSA-6mrr-q3pj-h53w across Packagist dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.

Scan my dependencies How O3 SCA works
GHSA-6mrr-q3pj-h53w: craftcms/cms | O3 Security