9.8
CRITICAL CVSS 3.1
CVE-2026-31946
OpenOLAT: Authentication bypass via forged JWT in OIDC implicit flow
Description

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.

INFO

Published Date :

March 30, 2026, 9:17 p.m.

Last Modified :

March 30, 2026, 9:17 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-31946 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 CRITICAL [email protected]
Solution
Update OpenOlat to version 20.2.5 or later to fix JWT signature verification.
  • Update OpenOlat to version 20.2.5 or newer.
  • Verify JWT signature validation is correctly configured.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-31946.

URL Resource
https://github.com/OpenOLAT/OpenOLAT/security/advisories/GHSA-v8vp-x4q4-2vch
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-31946 is associated with the following CWEs:

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-31946 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-31946 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Mar. 30, 2026

    Action Type Old Value New Value
    Added Description 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.
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
    Added CWE CWE-287
    Added CWE CWE-347
    Added Reference https://github.com/OpenOLAT/OpenOLAT/security/advisories/GHSA-v8vp-x4q4-2vch
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.