CVE-2025-6227Network attack vector

Synchronization payload injection via reused invite token

Published Jul 18, 2025 · Updated Jul 18, 2025

Insufficient credential protection in Mattermost 9.11.0 through 9.11.16 and 10.5.0 through 10.5.7 allows remote attackers to submit sync payloads. The remote-cluster invitation path stores the invitation token as the peer token instead of negotiating a fresh token when an invitation is accepted. Exploitation requires interception of both the invitation and its password; the reused token then authenticates REST API synchronization payloads to the originating server.

CVSS severity2.2
Low
EPSS probability0.18%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Insufficient credential protection in Mattermost 9.11.0 through 9.11.16 and 10.5.0 through 10.5.7 allows remote attackers to submit sync payloads. The remote-cluster invitation path stores the invitation token as the peer token instead of negotiating a fresh token when an invitation is accepted. Exploitation requires interception of both the invitation and its password; the reused token then authenticates REST API synchronization payloads to the originating server.

The record

CVE
CVE-2025-6227
Published
Jul 18, 2025
Updated
Jul 18, 2025
Vendor
Mattermost
Product
Mattermost
Classifications
CWE-522, T1550.001
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jul 18, 2025CVE publishedPublication date reported by the CVE source.
  2. Jul 18, 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.

  1. Affected versionversion=10.5.0 <=10.5.7
  2. Affected versionversion=9.11.0 <=9.11.16

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Mattermost · Mattermostversion=10.5.0 <=10.5.7; version=9.11.0 <=9.11.16

Published CVSS scores

2.2GitHub Advisory DatabaseCVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:L/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 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-522Insufficiently Protected Credentials
T1550.001Application Access Token

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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