Remote-cluster impersonation via reusable invite tokens
Published Dec 17, 2025 · Updated Dec 17, 2025
Incorrect authorization in affected Mattermost releases allows remote attackers to perform limited actions on shared channels. The remote-cluster confirmation flow leaves an invite token valid when legacy protocol version 1 is used or the confirming party supplies no refreshed token. Possession of an intercepted invite token is required; replay then authenticates the attacker as the remote cluster after legitimate confirmation, enabling bounded shared-channel changes.
Summary
What happened
Incorrect authorization in affected Mattermost releases allows remote attackers to perform limited actions on shared channels. The remote-cluster confirmation flow leaves an invite token valid when legacy protocol version 1 is used or the confirming party supplies no refreshed token. Possession of an intercepted invite token is required; replay then authenticates the attacker as the remote cluster after legitimate confirmation, enabling bounded shared-channel changes.
The record
- CVE
- CVE-2025-13324
- Published
- Dec 17, 2025
- Updated
- Dec 17, 2025
- Vendor
- Mattermost
- Product
- Mattermost
- Classifications
- CWE-863, T1550
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Dec 17, 2025CVE publishedPublication date reported by the CVE source.
- Dec 17, 2025Record 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=10.11.0 <=10.11.5
- Affected versionversion=10.12.0 <=10.12.2
- Affected versionversion=11.0.0 <=11.0.4
What conditions does exploitation require?
What is affected?
Published CVSS scores
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.
Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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