What is CVE-2026-123542?

CVE-2026-123542 is a medium-severity vulnerability in Openidentityplatform Openam, classified under CWE-358. CVSS score: 6.8/10. Published 2026-11-08.

How severe is CVE-2026-123542?

Medium severity. CVSS v3 base score is 6.8 out of 10.

Vulnerability in Openidentityplatform Openam

CVE-2026-123542

OpenAM before 16.1.4 fails to enforce PKCE in the OAuth 2.0 device authorization flow, never validating the code verifier when device codes are exchanged for tokens. Attackers who obtain an approved device code from client logs or shared device storage can redeem it for access and ID tokens to impersonate the user.

Published 2026-11-08.

CVSS v3 metric

CVSS v3 base score 6.8 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Openidentityplatform Openam

Weakness classification (CWE)

CWE-358

References

GitHub Security Advisory (GHSA-h93p-35jm-rj83) (vendor-advisory)
VulnCheck Advisory: OpenAM before 16.1.4 PKCE Bypass in OAuth 2.0 Device Authorization Flow (third-party-advisory)

Frequently asked questions

What is CVE-2026-123542?: CVE-2026-123542 is a medium-severity vulnerability in Openidentityplatform Openam, classified under CWE-358. CVSS score: 6.8/10. Published 2026-11-08.
How severe is CVE-2026-123542?: Medium severity. CVSS v3 base score is 6.8 out of 10.