CVE-2026-9802 | Keycloak: keycloak: unauthorized account access via replayed refresh tokens after cluster restart

A flaw was found in Keycloak. When revokeRefreshToken=true is enabled and persistent session storage is in use, a server restart can reset internal timing mechanisms. This allows a remote attacker, who has previously captured a user's refresh token, to replay that token even after it has been revoked. Successful exploitation grants the attacker unauthorized access to the victim's account, potentially leading to information disclosure or privilege escalation.

Published: 2026-05-28 Last update: 2026-06-03 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-9802 is rated Low Risk (31.9/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.04%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-9802

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-04 0.05% 0.04% -0.01%
2 2026-06-03 0.05% 0.05% +0.00%
3 2026-05-28 0.05%

Full EPSS history (3 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-9802

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.8 3.1 MEDIUM
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
1.6 5.2 [email protected]

Weakness enumeration for CVE-2026-9802

GitHub Security Advisory for CVE-2026-9802

GHSA-v5g5-wwmp-jppw · Severity: medium — A flaw was found in Keycloak. When revokeRefreshToken=true is enabled and persistent session...

OS Trackers for CVE-2026-9802

vendor priority summary link
redhat medium https://access.redhat.com/security/cve/CVE-2026-9802

Affected software / configurations for CVE-2026-9802

Vendor Product Version Raw CPE
redhat build_of_keycloak cpe:2.3:a:redhat:build_of_keycloak:-:*:*:*:-:*:*:*

References for CVE-2026-9802

cvelogic Threat Intelligence