CVE-2026-15571
CVE-2026-15571
A flaw was found in the legacy client-initiated account-linking endpoint of Keycloak, a widely used open-source identity and access management solution. The mechanism used to protect the account-linking process from unauthorized requests relies on a hash that can be predicted by a malicious OIDC client. By tricking a user into authenticating, an attacker-controlled client can forge a valid linking URL to connect the victim's account to an attacker's external identity. This results in a full account takeover, allowing the attacker to log in as the victim.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.3 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N.
EPSS exploit prediction
EPSS: 0.004 (35.0th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 35th percentile — 35.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.004 · change: +0.001
Weakness classification (CWE)
References
- access.redhat.com/errata/RHSA-2026:56523 (vendor-advisory)
- access.redhat.com/errata/RHSA-2026:56524 (vendor-advisory)
- access.redhat.com/security/cve/CVE-2026-15571 (vdb-entry)
- bugzilla.redhat.com/show_bug.cgi (issue-tracking)
Frequently asked questions
- What is CVE-2026-15571?
- CVE-2026-15571 is a high-severity vulnerability, classified under CWE-341. CVSS score: 7.3/10. Published 2026-08-18.
- How severe is CVE-2026-15571?
- High severity. CVSS v3 base score is 7.3 out of 10.