Security readout for executives and security teams
Plain-English summary
Craft CMS has an SSRF protection bypass in specific 4.x and 5.x versions. A user with GraphQL asset write permissions could cause the server to make unintended requests, potentially reaching cloud metadata or internal services over IPv6-only hostnames. This is not reported as actively exploited in the provided sources.
Executive priority
Treat as a timely patching item, especially for cloud-hosted Craft CMS sites with GraphQL enabled. Business urgency is moderate: exploitation requires permissions, but successful abuse could reach sensitive internal endpoints or metadata services.
Technical view
The GraphQL Asset mutation SSRF validation used gethostbyname(), which only resolves IPv4. IPv6-only AAAA hostnames return as strings, so blocklist comparison fails. This bypasses the prior CVE-2025-68437 fix. Affected versions are Craft CMS 4.5.0-RC1 through 4.16.18 and 5.0.0-RC1 through 5.8.22. Fixed in 4.16.19 and 5.8.23.
Likely exposure
Exposure is limited to Craft CMS deployments in affected ranges where GraphQL schemas allow editing and creating assets in a volume. Risk increases if Public Schema is misconfigured with write permissions. Internet-facing CMS instances with cloud metadata access deserve priority review.
Exploitation context
The CVE has network attack vector, low complexity, and requires low privileges. The provided sources do not show CISA KEV listing or confirmed active exploitation. Exploitability depends on GraphQL schema permissions and the ability to trigger asset mutation behavior.
Researcher notes
This is CWE-918 SSRF and a bypass of CVE-2025-68437 remediation. Focus review on hostname resolution logic, IPv6-only DNS behavior, GraphQL Asset mutations, and permission boundaries around volume asset creation and editing. Avoid assuming exposure without confirming schema permissions.
Mitigation direction
- Upgrade Craft CMS 4.x to 4.16.19 or later.
- Upgrade Craft CMS 5.x to 5.8.23 or later.
- Review GraphQL schemas for asset create and edit permissions.
- Ensure Public Schema does not grant write permissions unless explicitly required.
- Consult Craft CMS advisory guidance for any environment-specific hardening.
Validation and detection
- Inventory Craft CMS versions across all environments.
- Identify instances running 4.5.0-RC1 to 4.16.18.
- Identify instances running 5.0.0-RC1 to 5.8.22.
- Review GraphQL schema permissions for each asset volume.
- Check whether Public Schema has asset write permissions.
- Confirm upgraded instances report 4.16.19, 5.8.23, or later.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-918: Information exposure and cloud metadata lookup
Information exposure and SSRF weaknesses can make discovery, cloud metadata, and credential material review relevant. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCloud metadata behavior lookup
The CVE wording references SSRF or metadata access, so cloud discovery and credential material review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2026-27129 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 5.7 (4.0)
- Known Exploited
- No
- Published
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:P
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:P——Primary CVE scoreVulnerability scoring details
Base CVSS 4.0 score
5.7MediumVector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:P
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/craftcms/cms/security/advisories/GHSA-v2gc-rm6g-wrw9CVE reference · x_refsource_CONFIRM
- https://github.com/craftcms/cms/security/advisories/GHSA-x27p-wfqw-hfccCVE reference · x_refsource_MISC
- https://github.com/craftcms/cms/commit/2825388b4f32fb1c9bd709027a1a1fd192d709a3CVE reference · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Server-Side Request Forgery (SSRF)
Server-Side Request Forgery (SSRF) represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.