CVE-2026-31946

critical · 9.8

OpenOlat is an open source web-based e-learning platform for teaching, learning, assessment and communication. From version 10.5.4 to before version 20.2.5, OpenOLAT's OpenID Connect implicit flow implementation does not verify JWT signatures. The JSONWebToken.parse() method silently discards the signature segment of the compact JWT (header.payload.signature), and the getAccessToken() methods in both OpenIdConnectApi and OpenIdConnectFullConfigurableApi only validate claim-level fields (issuer, audience, state, nonce) without any cryptographic signature verification against the Identity Provider's JWKS endpoint. This issue has been patched in version 20.2.5.

9.8

CVSS

0.2%

EPSS (exploit prob.)

11th

EPSS percentile

2026-03-30

Published

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Weaknesses

CWE-287CWE-347

Affected products

Vendor	Product	Affected versions
frentix	openolat	>= 10.5.4, < 20.2.5

Check a specific version with /api/v1/cve/match.

References

https://github.com/OpenOLAT/OpenOLAT/security/advisories/GHSA-v8vp-x4q4-2vch

Query this programmatically:

curl https://evil-db.io/api/v1/cve/CVE-2026-31946