Craft is a content management system (CMS). In versions 4.5.0-RC1 through 4.16.18 and 5.0.0-RC1 through 5.8.22, 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. Versions 4.16.19 and 5.8.23 patch the issue.
CVE-2026-27128
This medium-severity CVE scores 4.8 under NVD CVSS v3. EPSS exploit probability: 0.2%, top 93% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).
- Lower severity and no public exploit yet
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 4.8
- EG Score
- 4.8(medium)
- EG Risk
- 26(Track)EG Risk 26/100SSVC: Track
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity48% × 45%Exploitation0% × 40%Automatability30% × 15%Action: Routine — remediate on your standard cadence. - EPSS PROB
- 0%
- EPSS %ILE
- 7%
- KEV
- Not listed
Published
February 24, 2026
Last Modified
June 17, 2026
Advisory Details (2)
Auto-updated Aug 4, 2026Race condition in Token Service potentially allows for token usage greater than the token limit · Advisory · craftcms/cms · GitHub
https://github.com/craftcms/cms/security/advisories/GHSA-6fx5-5cw5-4897commit 3e4afe182799 (craftcms/cms)
Patch available: craftcms/cms 6.0.0-alpha.3 (contains commit 3e4afe182799)
https://github.com/craftcms/cms/commit/3e4afe18279951c024c64896aa2b93cda6d95fdfAffected Packages
(1 across 1 ecosystem)
Packagist(1)
| Package | Vulnerable range | Fixed in | Dependents |
|---|---|---|---|
| craftcms/cms | 5.0.0 ... 5.8.9 (144 versions) | 5.8.23 | — |
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 7× in last 7d / 28× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-09-18 19:36 UTCOSV refresh
- 2026-09-18 19:28 UTCEPSS rescore
- 2026-09-18 19:27 UTCEPSS rescore
- 2026-09-17 19:30 UTCEPSS rescore
- 2026-09-16 14:08 UTCEPSS rescore
- 2026-09-16 05:15 UTCEPSS rescore
- 2026-09-13 16:47 UTCEPSS rescore
- 2026-09-12 15:01 UTCEPSS rescore
- 2026-09-11 14:52 UTCEPSS rescore
- 2026-09-10 09:34 UTCEPSS rescore
- 2026-09-08 22:00 UTCEPSS rescore
- 2026-09-07 16:01 UTCEPSS rescore
- 2026-09-06 13:47 UTCEPSS rescore
- 2026-09-06 13:47 UTCEPSS rescore
- 2026-09-04 05:06 UTCEPSS rescore
- 2026-09-02 14:11 UTCEPSS rescore
- 2026-09-01 13:53 UTCEPSS rescore
- 2026-09-01 04:39 UTCEPSS rescore
- 2026-08-30 22:47 UTCOSV refresh
- 2026-08-30 19:17 UTCEPSS rescore
- 2026-08-30 01:22 UTCEPSS rescore
- 2026-08-28 21:41 UTCEPSS rescore
- 2026-08-27 14:25 UTCEPSS rescore
- 2026-08-26 14:46 UTCEPSS rescore
- 2026-08-25 13:48 UTCEPSS rescore
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- 2026-08-23 00:19 UTCEPSS rescore
- 2026-08-21 23:49 UTCEPSS rescore
- 2026-08-20 22:55 UTCEPSS rescore
- 2026-08-19 17:03 UTCEPSS rescore
- 2026-08-18 13:48 UTCEPSS rescore
- 2026-08-17 13:47 UTCEPSS rescore
- 2026-08-16 14:56 UTCEPSS rescore
- 2026-08-16 02:14 UTCEPSS rescore
- 2026-08-15 01:30 UTCEPSS rescore
- 2026-08-14 09:09 UTCEG score recompute
- 2026-08-13 22:00 UTCEPSS rescore
- 2026-08-13 01:09 UTCEG score recompute
- 2026-08-12 13:50 UTCEPSS rescore
- 2026-08-11 13:42 UTCEPSS rescore
- 2026-08-11 07:58 UTCEG score recompute
- 2026-08-11 00:00 UTCEPSS rescore
- 2026-08-10 08:57 UTCEG score recompute
- 2026-08-09 13:46 UTCEPSS rescore
- 2026-08-07 20:54 UTCEG score recompute
- 2026-08-06 13:46 UTCEPSS rescore
- 2026-08-06 03:09 UTCEG score recompute
- 2026-08-05 19:17 UTCEPSS rescore
- 2026-08-04 15:10 UTCEPSS rescore
- 2026-08-04 06:00 UTCEG score recompute
- 2026-08-03 10:36 UTCEPSS rescore
- 2026-08-02 19:43 UTCEG score recompute
- 2026-08-02 02:26 UTCEPSS rescore
- 2026-08-01 04:16 UTCEPSS rescore
- 2026-07-30 16:27 UTCEPSS rescore
- 2026-07-30 01:30 UTCEPSS rescore
- 2026-07-28 15:36 UTCEPSS rescore
- 2026-07-27 13:34 UTCEG score recompute
Related CVEs(same CWE)
Frequently asked(5)
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Dependency Blast Radius
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