Vulnerability in Craftcms Cms
CVE-2026-27127
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, the SSRF validation in Craft CMS’s GraphQL Asset mutation performs DNS resolution separately from the HTTP request. This Time-of-Check-Time-of-Use (TOCTOU) vulnerability enables DNS rebinding attacks, where an attacker’s DNS server returns different IP addresses for validation compared to the actual request. This is a bypass of the security fix for CVE-2025-68437 that allows access to all blocked IPs, not just IPv6 endpoints. Exploitation requires GraphQL schema permissions for editing assets in the `<VolumeName>` volume and creating assets in the `<VolumeName>` volume. These permissions may be granted to authenticated users with appropriate GraphQL schema access and/or Public Schema (if misconfigured with write permissions). Versions 4.16.19 and 5.8.23 patch the issue.
Vulnerability class: TOCTOU (Time-of-Check to Time-of-Use)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.3 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N.
EPSS exploit prediction
EPSS: 0.004 (33.1th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 33rd percentile — 33.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: -0.000
Affected products
- Craftcms Cms — versions >= 4.5.0-RC1, < 4.16.19, >= 5.0.0-RC1, < 5.8.23
- Craftcms Craft Cms — versions 3.5.0, 5.0.0
Weakness classification (CWE)
References
- github.com/craftcms/cms/security/advisories/GHSA-gp2f-7wcm-5fhx (Exploit, Mitigation, Vendor Advisory)
- github.com/craftcms/cms/security/advisories/GHSA-x27p-wfqw-hfcc (Exploit, Patch, Vendor Advisory)
- github.com/craftcms/cms/commit/a4cf3fb63bba3249cf1e2882b18a2d29e77a8575 (Patch)
Frequently asked questions
- What is CVE-2026-27127?
- CVE-2026-27127 is a medium-severity vulnerability in Craftcms Cms, classified under Time-of-check Time-of-use (TOCTOU) Race Condition. CVSS score: 6.3/10. Published 2026-02-24.
- How severe is CVE-2026-27127?
- Medium severity. CVSS v3 base score is 6.3 out of 10.