CVE-2026-9802Network attack vector

Account access via post-restart refresh-token replay

Published May 28, 2026 · Updated May 28, 2026

Insufficient session expiration in Red Hat build of Keycloak allows remote attackers to access accounts with captured revoked refresh tokens. In refresh-token rotation validation, a restart advances the cluster startup time beyond the stored last-refresh timestamp, causing the stale-token check to skip rotated tokens. Exploitation requires revokeRefreshToken, persistent session storage, a server restart, and a previously captured token; acceptance returns a new access token for the victim's account.

CVSS severity6.8
Medium
EPSS probability0.30%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Insufficient session expiration in Red Hat build of Keycloak allows remote attackers to access accounts with captured revoked refresh tokens. In refresh-token rotation validation, a restart advances the cluster startup time beyond the stored last-refresh timestamp, causing the stale-token check to skip rotated tokens. Exploitation requires revokeRefreshToken, persistent session storage, a server restart, and a previously captured token; acceptance returns a new access token for the victim's account.

The record

CVE
CVE-2026-9802
Published
May 28, 2026
Updated
May 28, 2026
Vendor
389 Directory Server
Product
Red Hat build of Keycloak
Classifications
CWE-613, T1550.001
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 28, 2026CVE publishedPublication date reported by the CVE source.
  2. May 28, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected versions are unavailable in this record. Check the vendor advisory for version and patch details.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

389 Directory Server · Red Hat build of KeycloakAffected versions are unavailable in this record.

Published CVSS scores

6.8Red Hat, Inc.CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-613Insufficient Session Expiration
T1550.001Application Access Token

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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