4.3

CVE-2025-10545: mattermost Incorrect Authorization

CVSS: 4.3v3.1MediumAnalyzed
AliasesGHSA-424h-xj87-m937GO-2025-4030
Published 16-10-2025Last modified 16-10-2025
Open JSON

Vulnerability summary

CVE-2025-10545 is a medium (CVSS 4.3) Incorrect Authorization vulnerability in mattermost. EPSS estimates a 0.33% chance of exploitation in the next 30 days, higher than 24.3% of scored vulnerabilities.

Overall risk
17/100
0100
Low · default modelHow is this calculated?
CVSS score
4.3/10
010
Medium · v3.1 (NVD)
EPSS score
0.33%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 2 · Related 2
OPENSUSE-SU-2025:15710-1OPENSUSE-SU-2026:21483-1

Timeline

  1. 16-10-2025
    PublishedVulnerability first disclosed.
  2. 16-10-2025
    Last modifiedVulnerability information updated.

Description

Mattermost versions 10.5.x <= 10.5.10, 10.11.x <= 10.11.2 fail to properly validate guest user permissions when adding channel members which allows guest users to add any team members to their private channels via the `/api/v4/channels/{channel_id}/members` endpoint

CVSS metrics

3 scores · 3 sources · 1 version

EPSS trend

Probability

0.33%

Chance of exploitation in the next 30 days

Percentile

24%

Versus all other CVEs

30-day change

0.00 pp

From 0.32% on 21-09-2026

21-09-202621-10-2026
EPSS score
0.33%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Github.com/mattermost/mattermost-server2 products
  • v5All versions (No fix recorded)
  • v6All versions (No fix recorded)
Mattermost2 products
Github.com/mattermost1 product
  • mattermost-server≥ 10.5.0, < 10.5.11 | ≥ 10.11.0, < 10.11.3 | ≥ 10.11.0+incompatible, < 10.11.3+incompatible
Github.com/mattermost/mattermost/server1 product
  • v8< 8.0.0-20250820115038-ff30b84049f0

4 vendors · 6 products

References

8 links