CVE-2025-27370

medium

Description

OpenID Connect Core through 1.0 errata set 2 allows audience injection in certain situations. When the private_key_jwt authentication mechanism is used, a malicious Authorization Server could trick a Client into writing attacker-controlled values into the audience, including token endpoints or issuer identifiers of other Authorization Servers. The malicious Authorization Server could then use these private key JWTs to impersonate the Client.

References

https://talks.secworkshop.events/osw2025/talk/R8D9BS/

https://openid.net/wp-content/uploads/2025/01/OIDF-Responsible-Disclosure-Notice-on-Security-Vulnerability-for-private_key_jwt.pdf

https://openid.net/notice-of-a-security-vulnerability/

https://github.com/OWASP/ASVS/issues/2678

https://eprint.iacr.org/2025/629

Details

Source: Mitre, NVD

Published: 2025-03-03

Updated: 2026-04-15

Risk Information

CVSS v2

Base Score: 6.1

Vector: CVSS2#AV:N/AC:H/Au:N/C:P/I:C/A:N

Severity: Medium

CVSS v3

Base Score: 6.9

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

Severity: Medium

EPSS

EPSS: 0.00055