How severe is CVE-2026-31946?

CVE-2026-31946 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-31946 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (11th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-31946?

CVE-2026-31946 affects Frentix Openolat. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-31946?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

Does CVE-2026-31946 have an EU (EUVD) identifier?

Yes. CVE-2026-31946 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-17207.

When was CVE-2026-31946 published?

CVE-2026-31946 was published on 2026-03-30 and last updated on 2026-06-17.

CVE-2026-31946

CVE-2026-31946 is a critical-severity vulnerability in Frentix Openolat with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-287.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 0% (11th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-17207
Weakness: CWE-287
Affected product: Frentix Openolat
Published: 2026-03-30
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2026-31946?: 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.
How severe is CVE-2026-31946?: CVE-2026-31946 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-31946 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (11th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-31946?: CVE-2026-31946 affects Frentix Openolat. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-31946?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2026-31946 have an EU (EUVD) identifier?: Yes. CVE-2026-31946 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-17207.
When was CVE-2026-31946 published?: CVE-2026-31946 was published on 2026-03-30 and last updated on 2026-06-17.

References

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

Affected products (1)

cpe:2.3:a:frentix:openolat:*:*:*:*:*:*:*:*

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