6.5

CVE-2025-6226: IDOR in CreatePost API allows for timeboxed message disclosure

Analyzed
AliasesGHSA-7h34-9chr-58qhGO-2025-3819
Published 18-07-2025Last modified 07-08-2025

Vulnerability summary

CVE-2025-6226 is a medium (CVSS 6.5) vulnerability in mattermost. EPSS estimates a 0.37% chance of exploitation in the next 30 days, higher than 31.1% of scored vulnerabilities.

Priority
Routine

Not severe (CVSS 6.5, network access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
6.5/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.37%
0%100%
Low · +0.06 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 1 · Related 1
OPENSUSE-SU-2025:15405-1

Timeline

  1. 18-07-2025
    PublishedVulnerability first disclosed.
  2. 07-08-2025
    Last modifiedVulnerability information updated.

Description

Mattermost versions 10.5.x <= 10.5.6, 10.8.x <= 10.8.1, 10.7.x <= 10.7.3, 9.11.x <= 9.11.16 fail to verify authorization when retrieving cached posts by PendingPostID which allows an authenticated user to read posts in private channels they don't have access to via guessing the PendingPostID of recently created posts.

CVSS metrics

3 scores · 3 sources · 1 version

EPSS trend

Probability

0.37%

Chance of exploitation in the next 30 days

Percentile

31%

Versus all other CVEs

30-day change

Increase +0.06 pp

From 0.32% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: network-reachable, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.

Github.com/mattermost/mattermost-server2 products
  • v5All versions (No fix recorded)
  • v6All versions (No fix recorded)
Mattermost2 products
  • mattermost≥ 10.5.0, ≤ 10.5.6 | ≥ 10.8.0, ≤ 10.8.1 | ≥ 10.7.0, ≤ 10.7.3 | ≥ 9.11.0, ≤ 9.11.16
  • mattermost_server≥ 9.11.0, < 9.11.17 | ≥ 10.5.0, < 10.5.7 | ≥ 10.7.0, < 10.7.4 | ≥ 10.8.0, < 10.8.2
Github.com/mattermost1 product
  • mattermost-server≥ 10.5.0, < 10.5.7 | ≥ 10.8.0, < 10.8.2 | ≥ 10.7.0, < 10.7.4 | ≥ 9.11.0, < 9.11.17 | ≥ 10.8.0+incompatible, < 10.8.2+incompatible
Github.com/mattermost/mattermost/server1 product
  • v8< 8.0.0-20250520130510-fa40a8c5d47f

4 vendors · 6 products

References

5 links