How widely exploitable is this vulnerability?

The vulnerability can affect any OpenOlat deployment using the OpenID Connect implicit flow in the impacted versions, especially when exposed to the internet. Exploitability increases significantly if an attacker can directly interact with the OIDC callback endpoint, control an OIDC client configuration, or interfere with communication between the Identity Provider and OpenOlat.

What level of access does an attacker need to exploit this?

The attacker needs the ability to send or influence OIDC authentication responses received by OpenOlat. This could be achieved by operating a malicious or misconfigured OIDC client, crafting requests to the redirect URI, or in some environments by being able to intercept and modify responses in transit. Direct access to the application or network-level control is not always required if the callback endpoint is reachable and insufficiently constrained.

What is the safest general fix pattern?

The safest approach is to enforce strict JWT signature verification for all ID tokens and access tokens before treating them as valid credentials. This means using a JWT library that requires verification keys, validating against the Identity Provider's JWKS, restricting accepted algorithms, and treating any failure in signature or claim validation as a hard authentication failure.

Severity:

CRITICAL RISK

(9.8)

Missing JWT Signature Verification (CWE-347) in OpenOlat OpenID Connect Implicit Flow

CVE-2026-31946

Published:

Mar 30, 2026

Status:

Analyzed

Summary

Affected Context

Exploit Preconditions

Why This Happens

Potential Impact

General Mitigation Guidance

How Teams Detect Issues Like This

Frequently Asked Questions

Source

NDV

Recent Vulnerabilities

CWE-77;CWE-78

HIGH RISK

HIGH

(7.3)

OS Command Injection (CWE-78) in Totolink A7100RU setGameSpeedCfg CGI Handler

Remote Code Execution on the Router

April 6, 2026

CWE-77;CWE-78

HIGH RISK

HIGH

(7.3)

OS Command Injection (CWE-78) in Totolink A7100RU setFirewallType Handler

Remote Code Execution on Router Firmware

April 6, 2026

Vulnerability Type

Category:

Authentication and Token Validation Flaws

CWE:

CWE-287;CWE-347

Impact:

Authentication Bypass and Unauthorized Access

Severity:

CRITICAL RISK

(9.8)

CVSS Version:

3.1

Vulnerability Type

Category:

Authentication and Token Validation Flaws

CWE:

CWE-287;CWE-347

Impact:

Authentication Bypass and Unauthorized Access

Severity:

CRITICAL RISK

(9.8)

CVSS Version:

3.1

Catch This CVE While Code Is Being Written

Detect vulnerable code directly in pull requests, so CVEs are fixed before merge.

Get Started

Ship clean & secure code faster

START 14 DAYS FREE TRIAL

BOOK A DEMO

Made with Love in San Francisco

355 Bryant St. San Francisco, CA 94107, USA

Ask AI for summary of CodeAnt

Made with Love in San Francisco

355 Bryant St. San Francisco, CA 94107, USA

Ask AI for summary of CodeAnt

Made with Love in San Francisco

355 Bryant St. San Francisco, CA 94107, USA

Ask AI for summary of CodeAnt

Missing JWT Signature Verification (CWE-347) in OpenOlat OpenID Connect Implicit Flow

Summary

Affected Context

Exploit Preconditions

Why This Happens

Potential Impact

General Mitigation Guidance

How Teams Detect Issues Like This

Frequently Asked Questions

Source

Recent Vulnerabilities

HIGH RISK

HIGH

(7.3)

OS Command Injection (CWE-78) in Totolink A7100RU setGameSpeedCfg CGI Handler

HIGH RISK

HIGH

(7.3)

OS Command Injection (CWE-78) in Totolink A7100RU setFirewallType Handler

Vulnerability Type

Vulnerability Type

Vulnerability Type

Catch This CVE While Code Is Being Written

Ship clean & secure code faster

Product

Pricing

Company

Legal

Developers

Compare

Product

Pricing

Company

Legal

Developers

Compare

Product

Pricing

Company

Legal

Developers

Compare