CVE-2023-1775 - CVE House
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Status published Medium CVE-2023-1775

Unsanitized events sent over Websocket to regular users in a High Availability environment

Vulnerability Description

When running in a High Availability configuration, Mattermost fails to sanitize some of the user_updated and post_deleted events broadcast to all users, leading to disclosure of sensitive information to some of the users with currently connected Websocket clients.

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:

  • Kyriakos Ziakoulis
  • Harrison Healey

References

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Affected Vendor

Affected Software

Mattermost
Vulnerable Versions:
3.3.0, 7.8.0, 7.7.2, 7.1.6

Timeline

Official Publish: March 31st, 2023
Last Modified: December 6th, 2024
Added to House: July 22nd, 2026

CVSS Vectors

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

Weaknesses (CWE)

CWE-200

MITRE ATT&CK TTPs

T1213 Data from Information Repositories
Collection
T1005 Data from Local System
Collection
T1552 Unsecured Credentials
Credential Access
T1041 Exfiltration Over C2 Channel
Exfiltration