5.7

CVE-2025-13821: mattermost

CVSS: 5.7v3.1MediumAnalyzed
AliasesGHSA-pp9j-pf5c-659xGO-2026-4524
Published 16-02-2026Last modified 17-02-2026
Open JSON

Vulnerability summary

CVE-2025-13821 is a medium (CVSS 5.7) vulnerability in mattermost. EPSS estimates a 0.24% chance of exploitation in the next 30 days, higher than 13.9% of scored vulnerabilities.

Overall risk
23/100
0100
Low · default modelHow is this calculated?
CVSS score
5.7/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.24%
0%100%
Low · +0.03 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-2026:21483-1SUSE-SU-2026:0757-1

Timeline

  1. 16-02-2026
    PublishedVulnerability first disclosed.
  2. 17-02-2026
    Last modifiedVulnerability information updated.

Description

Mattermost versions 11.1.x <= 11.1.2, 10.11.x <= 10.11.9, 11.2.x <= 11.2.1 fail to sanitize sensitive data in WebSocket messages which allows authenticated users to exfiltrate password hashes and MFA secrets via profile nickname updates or email verification events. Mattermost Advisory ID: MMSA-2025-00560

CVSS metrics

3 scores · 3 sources · 1 version

EPSS trend

Probability

0.24%

Chance of exploitation in the next 30 days

Percentile

14%

Versus all other CVEs

30-day change

+0.03 pp

From 0.21% on 20-09-2026

20-09-202620-10-2026
EPSS score
0.24%

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
  • mattermost≥ 11.1.0, ≤ 11.1.2 | ≥ 10.11.0, ≤ 10.11.9 | ≥ 11.2.0, ≤ 11.2.1
  • mattermost_server≥ 10.11.0, < 10.11.10 | ≥ 11.1.0, < 11.1.3 | ≥ 11.2.0, < 11.2.2
Github.com/mattermost1 product
  • mattermost-server≥ 11.1.0 (No fix recorded) | ≥ 10.11.0 (No fix recorded) | ≥ 11.2.0 (No fix recorded) | < 5.3.2-0.20251210191531-cd17b61de41b | All versions (No fix recorded) | ≥ 10.11.0+incompatible (No fix recorded) | ≥ 11.1.0+incompatible (No fix recorded) | ≥ 11.2.0+incompatible (No fix recorded)
Github.com/mattermost/mattermost/server1 product
  • v8< 8.0.0-20251210191531-cd17b61de41b

4 vendors · 6 products

References

5 links