Server-side Request Forgery (SSRF) Affecting craftcms/cms package, versions >=3.5.0, <4.16.19>=5.0.0-RC1, <5.8.23
Threat Intelligence
Snyk has a proof-of-concept or detailed explanation of how to exploit this vulnerability.
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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- published24 Feb 2026
- disclosed24 Feb 2026
- creditRaj Chowdhury, rlarabee
Introduced: 24 Feb 2026
CVE-2026-27129 (opens in a new tab)How to fix?
Upgrade craftcms/cms to version 4.16.19, 5.8.23 or higher.
Overview
craftcms/cms is a content management system.
Affected versions of this package are vulnerable to Server-side Request Forgery (SSRF) in the gethostbyname function used during GraphQL Asset mutation processing. An attacker can access internal cloud metadata endpoints by supplying hostnames that resolve only to IPv6 addresses, thereby bypassing SSRF protection through crafted GraphQL requests.
Notes:
This is only exploitable if the attacker has GraphQL schema permissions for editing or creating assets in the relevant volume, which may be granted to authenticated users or, if misconfigured, to the public schema.
This is a bypass of the security fix for CVE-2025-68437.