How severe is GHSA-6fx5-5cw5-4897?

No CVSS score has been assigned to GHSA-6fx5-5cw5-4897 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by GHSA-6fx5-5cw5-4897?

GHSA-6fx5-5cw5-4897 affects the following packages: craftcms/cms (Packagist), craftcms/cms (Packagist). Ecosystems affected: Packagist.

How do I fix GHSA-6fx5-5cw5-4897?

Update craftcms/cms to 4.16.19 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-6fx5-5cw5-4897 is resolved across your whole dependency graph.

How do I detect GHSA-6fx5-5cw5-4897 in my Packagist dependencies?

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.

How do I mitigate GHSA-6fx5-5cw5-4897 if there is no patch (or I can't update yet)?

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.

How does O3 Security protect against GHSA-6fx5-5cw5-4897?

O3 pinpoints whether GHSA-6fx5-5cw5-4897 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is GHSA-6fx5-5cw5-4897 actively exploited in the wild?

No public exploit code has been indexed for GHSA-6fx5-5cw5-4897 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 GHSA-6fx5-5cw5-4897?

GHSA-6fx5-5cw5-4897 has an EPSS (Exploit Prediction Scoring System) score of 0.2%, placing it in the 7th 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 GHSA-6fx5-5cw5-4897?

GHSA-6fx5-5cw5-4897 is classified as CWE-367 (CWE-367). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was GHSA-6fx5-5cw5-4897 published, and has it been updated?

GHSA-6fx5-5cw5-4897 was published on February 23, 2026 and was last updated on February 24, 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

GHSA-6fx5-5cw5-4897

Craft CMS Race condition in Token Service potentially allows for token usage greater than the token limit

Also known asCVE-2026-27128

Published

Feb 23, 2026

Updated

Feb 24, 2026

Affected

2 pkgs

Patched

2 / 2

Exploits

None indexed

EPSS Exploitation Probability

via FIRST.org ↗

0.2%probability of exploitation in next 30 days

Lower Risk7th percentile+0.17%

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.

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

A Time-of-Check-Time-of-Use (TOCTOU) race condition exists in Craft CMS’s token validation service for tokens that explicitly set a limited usage. The getTokenRoute() method reads a token’s usage count, checks if it’s within limits, then updates the database in separate non-atomic operations. By sending concurrent requests, an attacker can use a single-use impersonation token multiple times before the database update completes.

To make this work, an attacker needs to obtain a valid user account impersonation URL with a non-expired token via some other means and exploit a race condition while bypassing any rate-limiting rules in place.

For this to be a privilege escalation, the impersonation URL must include a token for a user account with more permissions than the current user.

References

https://github.com/craftcms/cms/commit/3e4afe18279951c024c64896aa2b93cda6d95fdf

Affected Packages

2 total 2 fixed

Ecosystem	Package	Vulnerable range	Fix
🐘Packagist	`craftcms/cms`	≥ 4.5.0-RC1&&< 4.16.19	4.16.19
🐘Packagist	`craftcms/cms`	≥ 5.0.0-RC1&&< 5.8.23	5.8.23

Detection & mitigation playbook

Open-source dependency

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.
Fix
Update craftcms/cms to 4.16.19 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-6fx5-5cw5-4897 is resolved across your whole dependency graph.
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.
How O3 protects you
O3 pinpoints whether GHSA-6fx5-5cw5-4897 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 GHSA-6fx5-5cw5-4897. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

A Time-of-Check-Time-of-Use (TOCTOU) race condition exists in Craft CMS’s token validation service for tokens that explicitly set a limited usage. The `getTokenRoute()` method reads a token’s usage count, checks if it’s within limits, then updates the database in separate non-atomic operations. By sending concurrent requests, an attacker can use a single-use impersonation token multiple times before the database update completes. To make this work, an attacker needs to obtain a valid user account impersonation URL with a non-expired token via some other means and exploit a race condition whil

O3 Security · Impact-Aware SCA

Is GHSA-6fx5-5cw5-4897 in your dependencies?

O3 detects GHSA-6fx5-5cw5-4897 across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

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