CVE-2024-39274 - CVE House
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Status published High CVE-2024-39274

Malicious remote can add users to arbitrary teams and channels

Vulnerability Description

Mattermost versions 9.9.x <= 9.9.0, 9.5.x <= 9.5.6, 9.7.x <= 9.7.5 and 9.8.x <= 9.8.1 fail to properly validate that the channel that comes from the sync message is a shared channel, when shared channels are enabled, which allows a malicious remote to add users to arbitrary teams and channels

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:

  • Juho Forsén

References

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Affected Vendor

Affected Software

Mattermost
Vulnerable Versions:
9.9.0, 9.5.0, 9.7.0, 9.8.0, 9.10.0, 9.9.1, 9.5.7, 9.7.6, 9.8.2

Timeline

Official Publish: August 1st, 2024
Last Modified: August 2nd, 2024
Added to House: July 22nd, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N

Weaknesses (CWE)

CWE-284

MITRE ATT&CK TTPs

T1190 Exploit Public-Facing Application
Initial Access
T1068 Exploitation for Privilege Escalation
Privilege Escalation
T1078 Valid Accounts
Persistence
T1213 Data from Information Repositories
Collection
T1565.002 Stored Data Manipulation
Impact