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.

CVSS

No CVSS.

References

Link	Resource
https://github.com/microsoft/o365-moodle/commit/01b2d4c2e13b06a66557527084cbf9bace655944
https://github.com/microsoft/o365-moodle/commit/258872f6e2011f4efa8ebb77d2898142a9435e89
https://github.com/microsoft/o365-moodle/commit/d5596655f0baaee0f11aec2e10d6f36b0bd29220
https://github.com/microsoft/o365-moodle/releases/tag/v20260423_m405
https://github.com/microsoft/o365-moodle/releases/tag/v20260423_m500
https://github.com/microsoft/o365-moodle/releases/tag/v20260423_m501
https://github.com/microsoft/o365-moodle/security/advisories/GHSA-hqjh-93qv-47v5

Configurations

No configuration.

History

16 Jul 2026, 16:19

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-16 16:19

Updated : 2026-07-16 17:46

NVD link : CVE-2026-54733

Mitre link : CVE-2026-54733

CVE.ORG link : CVE-2026-54733

JSON object : View

Products Affected

No product.

CWE

CWE-347

Improper Verification of Cryptographic Signature

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