CVE-2025-53910 | Unauthorized Channel Subscription Edit in Mattermost Confluence Plugin

Mattermost Confluence Plugin version <1.5.0 fails to check the access of the user to the channel which allows attackers to create a channel subscription without proper access to the channel via API call to the edit channel subscription endpoint.

Published: 2025-08-11 Last update: 2025-09-25 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2025-53910 is rated Low Risk (31.3/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.21%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2025-53910

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-07 0.05% 0.21% +0.16%
2 2026-04-27 0.03% 0.05% +0.02%
3 2026-01-07 0.03%

Full EPSS history (5 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-53910

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
4.0 3.1 MEDIUM
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
2.2 1.4 [email protected]

Weakness enumeration for CVE-2025-53910

GitHub Security Advisory for CVE-2025-53910

GHSA-v6c8-g53h-mc2h · Severity: medium · Ecosystem: go — Mattermost Confluence Plugin has Missing Authorization vulnerability

Affected software / configurations for CVE-2025-53910

Vendor Product Version Raw CPE
mattermost confluence < 1.5.0 cpe:2.3:a:mattermost:confluence:*:*:*:*:*:mattermost:*:*

References for CVE-2025-53910

URL Tags
https://mattermost.com/security-updates Vendor Advisory
cvelogic Threat Intelligence