CVE-2026-92591
Medium CVSS 5.9Published 2026-09-16 · last changed 2026-09-17
The fix
We hold no Microsoft remediation data for CVE-2026-92591, which normally means it is not a Windows CVE. For non-Microsoft software the fix is the vendor's own updated release, and the affected versions are listed below.
What it is
Craft CMS 5.0.0 through 5.10.12 treats a database connection failure as meaning that Craft is not installed, which makes anonymous installer actions — including install/validate-site — reachable on an installed production site whenever PHP remains available but the configured MySQL endpoint does not. The action accepts a site name, serializes it through Site::getName(), and expands ${NAME} expressions using App::env(). An unauthenticated attacker who obtained a guest session cookie and matching CSRF token before the outage and whose session remains valid during it can submit a predictable variable name (for example Craft's conventional CRAFT_SECURITY_KEY) and receive its value, disclosing Craft secrets, process environment variables, $_SERVER entries, or PHP constants such as the security key, database credentials, or API keys. The issue requires an independently occurring database outage; the vulnerability itself provides no way to induce it. Fixed in 5.10.13.
Sources
CVSS vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N