SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2026-9087

A flaw was found in Keycloak.

HIGH 8.1EPSS 0.31%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.31%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

A flaw was found in Keycloak. The cross-session verification proof is keyed only by (local userId, idpAlias) and is not bound to the upstream identity that was actually verified, so a second upstream account on the same IdP can consume it and get linked to the victim's local account.

CVSS 3.1
8.1 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N
EPSS
0.31% probability · 24th percentile
CISA KEV
Not listed
Weakness
CWE-639
Affected
redhat/build of keycloak
Source
secalert@redhat.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.