Vulnerability in Microsoft O365-Moodle
CVE-2026-54733
The Microsoft 365 and Microsoft Entra ID Plugins for Moodle provide Office 365 and Azure Active Directory integration for Moodle. Prior to 4.5.6, 5.0.5, and 5.1.1, the Microsoft Office 365 Integration plugin local_o365 Teams SSO endpoint sso_login.php base64-decodes a JWT payload and authenticates users from the upn claim without verifying the JWT signature, allowing an unauthenticated attacker to forge a token and obtain a Moodle session as an O365-authenticated user. This issue is fixed in versions 4.5.6, 5.0.5, and 5.1.1.
Published · last modified .
EPSS exploit prediction
EPSS: 0.009 (58.6th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 59th percentile — 58.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.009 · newest: 0.009 · change: 0.000
Affected products
- Microsoft O365-Moodle — versions < 4.5.6, >= 5.0.0, < 5.0.5, >= 5.1.0, < 5.1.1
Weakness classification (CWE)
References
- github.com/microsoft/o365-moodle/security/advisories/GHSA-hqjh-93qv-47v5
- github.com/microsoft/o365-moodle/commit/01b2d4c2e13b06a66557527084cbf9bace655944
- github.com/microsoft/o365-moodle/commit/258872f6e2011f4efa8ebb77d2898142a9435e89
- github.com/microsoft/o365-moodle/commit/d5596655f0baaee0f11aec2e10d6f36b0bd29220
- github.com/microsoft/o365-moodle/releases/tag/v20260423_m405
- github.com/microsoft/o365-moodle/releases/tag/v20260423_m500
- github.com/microsoft/o365-moodle/releases/tag/v20260423_m501