CVE-2026-15943: Keycloak-services: keycloak-services: oidc idp update reuses masked client secret after token url change
Vulnerability summary
CVE-2026-15943 is a medium (CVSS 5.5) vulnerability in redhat build_of_keycloak. EPSS estimates a 0.34% chance of exploitation in the next 30 days, higher than 25.8% of scored vulnerabilities.
Timeline
- 17-07-2026PublishedVulnerability first disclosed.
- 31-08-2026Last modifiedVulnerability information updated.
Description
A flaw was found in the Keycloak keycloak-services component, which handles the management of identity providers. The issue occurs when a delegated administrator updates an OIDC identity provider using a masked client secret sentinel value. Due to improper validation, Keycloak reuses the existing real secret even if security-sensitive fields like the token URL have been changed, allowing an attacker to redirect and capture the secret.
CVSS metrics
2 scores · 2 sources · 1 version- NVDNIST5.5MediumCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:L/A:N
EPSS trend
Probability
0.34%
Chance of exploitation in the next 30 days
Percentile
26%
Versus all other CVEs
30-day change
No change 0.00 pp
From 0.34% on 22-09-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Redhat1 product
1 vendor · 1 product