CVE-2025-0503

Leaked User IDs and Metadata of Deleted DMs

Description

Mattermost versions 9.11.x <= 9.11.6 fail to filter out DMs from the deleted channels endpoint which allows an attacker to infer user IDs and other metadata from deleted DMs if someone had manually marked DMs as deleted in the database.

Remediation

Solution:

  • Update Mattermost to versions 10.4.0, 9.11.7 or higher.

Category

3.1
CVSS
Severity: Low
CVSS 3.1 •
EPSS 0.04%
Affected: Mattermost Mattermost
Published at:
Updated at:

References

Link Tags
https://mattermost.com/security-updates

Frequently Asked Questions

What is the severity of CVE-2025-0503?
CVE-2025-0503 has been scored as a low severity vulnerability.
How to fix CVE-2025-0503?
To fix CVE-2025-0503: Update Mattermost to versions 10.4.0, 9.11.7 or higher.
Is CVE-2025-0503 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2025-0503 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2025-0503?
CVE-2025-0503 affects Mattermost Mattermost.
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