Cross-user token deletion via mismatched authorization key
Published Aug 28, 2026 · Updated Aug 28, 2026
Authorization bypass in Graylog Open Server allows remote authenticated users to delete other users' access tokens through the REST API. UsersResource.revokeToken checks USERS_TOKENREMOVE against the userId path value, then resolves idOrToken and destroys the resulting token without verifying its owner. A valid account and a known or guessed token identifier are required; token contents remain undisclosed, but deletion can interrupt access-token-based integrations.
Summary
What happened
Authorization bypass in Graylog Open Server allows remote authenticated users to delete other users' access tokens through the REST API. UsersResource.revokeToken checks USERS_TOKENREMOVE against the userId path value, then resolves idOrToken and destroys the resulting token without verifying its owner. A valid account and a known or guessed token identifier are required; token contents remain undisclosed, but deletion can interrupt access-token-based integrations.
The record
- CVE
- CVE-2026-55867
- Published
- Aug 28, 2026
- Updated
- Aug 28, 2026
- Vendor
- Graylog
- Product
- Graylog Open Server
- Classifications
- CWE-639, T1531
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Aug 28, 2026CVE publishedPublication date reported by the CVE source.
- Aug 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?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=>= 6.2.0, < 6.3.12
- Affected versionversion=>= 7.0.0-alpha.1, < 7.0.7
- Affected versionversion=>= 7.1.0-alpha.1, < 7.1.2
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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