CVE-2025-53857 | Lack of Authorization on Get Channel Subscriptions for Autocomplete 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 get channel subscription details without proper access to the channel via API call to the GET autocomplete/GetChannelSubscriptions endpoint.

Published: 2025-08-11 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2025-53857 is rated Low Risk (29.6/100): CVSS Low severity, with low exploitation likelihood (EPSS 0.20%). 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-2025-53857

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% 0.20% +0.15%
2 2026-05-07 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-2025-53857

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
3.7 3.1 LOW
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/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:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 2.2 1.4 [email protected]

Weakness enumeration for CVE-2025-53857

GitHub Security Advisory for CVE-2025-53857

GHSA-42m6-5vm7-fjv2 · Severity: low · Ecosystem: go — Mattermost Confluence Plugin has Missing Authorization vulnerability

Affected software / configurations for CVE-2025-53857

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

References for CVE-2025-53857

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