Summary
Graylog token revocation endpoint allows authenticated users to delete other users’ access tokens
Workarounds
There are no feasible workarounds for this issue. Upgrading to a patched version is recommended.
Customers using Graylog Enterprise or Security can review the audit log^1 for suspicious activity. Audit log lines for successful token deletions begin with access token deleted from user.
Credits
Thanks to michaelddickenson and sreelim for reporting.
Impact
Graylog contains an insecure direct object reference (IDOR) vulnerability in the token revocation endpoint. An authenticated user can delete access tokens belonging to other users, including service account tokens and administrator tokens, if they know or can guess a valid token identifier.
The issue does not expose token contents, but it allows unauthorized token deletion, leading to integrity impact and potential availability impact for access token based integrations.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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The issue has been fixed in the following Graylog versions: 6.3.12, 7.0.7, 7.1.2. Users should upgrade to one of these versions or above to remediate the vulnerability.
Graylog Cloud has already been patched.
Frequently Asked Questions
- What is CVE-2026-55867? CVE-2026-55867 is a medium-severity security vulnerability in org.graylog2:graylog2-server (maven), affecting versions >= 6.2.0, < 6.3.12. It is fixed in 6.3.12, 7.0.7, 7.1.2.
- Which versions of org.graylog2:graylog2-server are affected by CVE-2026-55867? org.graylog2:graylog2-server (maven) versions >= 6.2.0, < 6.3.12 is affected.
- Is there a fix for CVE-2026-55867? Yes. CVE-2026-55867 is fixed in 6.3.12, 7.0.7, 7.1.2. Upgrade to this version or later.
- Is CVE-2026-55867 exploitable, and should I be worried? Whether CVE-2026-55867 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2026-55867 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2026-55867?
- Upgrade
org.graylog2:graylog2-serverto 6.3.12 or later - Upgrade
org.graylog2:graylog2-serverto 7.0.7 or later - Upgrade
org.graylog2:graylog2-serverto 7.1.2 or later
- Upgrade