Description
A flaw was found in Keycloaks OpenID Connect user authentication, which may incorrectly authenticate requests. An authenticated attacker who could obtain information from a user request within the same realm could use that data to impersonate the victim and generate new session tokens. This issue could impact confidentiality, integrity, and availability.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| redhat.com | Keycloak | 18.0.6 – < 18.0.6 | 18.0.6 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Red Hat Single Sign On 7 | rh-sso7-keycloak +1 | 18.0.6-1.redhat_00001.1.el7sso | RHSA-2023:1045, RHSA-2023:1044, RHSA-2023:1043 |
Public exploits
Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.
GitHub 2 repositories
-
twwd/CVE-2023-0264 ★ 7 · Mar 6, 2023
A small PoC for the Keycloak vulnerability CVE-2023-0264
-
ElianGonzi00/pocKeycloakCVE-2023-0264 ★ 0 · Jul 28, 2026
Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| Maven | org.keycloak:keycloak-services | < 21.0.1 | 21.0.1 | GHSA-9g98-5mj6-f9mv |
Advisories 4
- RHSA-2023:1045 Red Hat Security Advisory: Red Hat Single Sign-On 7.6.2 security update on RHEL 9 Red Hat Security Advisories (RHSA) · Oct 13, 2026
- RHSA-2023:1044 Red Hat Security Advisory: Red Hat Single Sign-On 7.6.2 security update on RHEL 8 Red Hat Security Advisories (RHSA) · Oct 13, 2026
- RHSA-2023:1043 Red Hat Security Advisory: Red Hat Single Sign-On 7.6.2 security update on RHEL 7 Red Hat Security Advisories (RHSA) · Oct 13, 2026
- WID-SEC-2023-0562 Keycloak: Mehrere Schwachstellen BSI CERT-Bund (WID) · Oct 3, 2023