CVE-2025-13321

Local data disclosure via verbose logging and retention

Published Dec 17, 2025 · Updated Dec 17, 2025

Sensitive-data exposure in Mattermost Desktop App before 6.0.0 allows local users to read potentially sensitive data from application logs. Multiple Electron handlers logged complete URLs, server objects, download items, paths, and error objects, while server removal omitted session-storage cleanup. Access to the user's local files is required; exposure is limited to values recorded in logs or retained for a removed server.

CVSS severity3.3
Low
EPSS probability0.12%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Sensitive-data exposure in Mattermost Desktop App before 6.0.0 allows local users to read potentially sensitive data from application logs. Multiple Electron handlers logged complete URLs, server objects, download items, paths, and error objects, while server removal omitted session-storage cleanup. Access to the user's local files is required; exposure is limited to values recorded in logs or retained for a removed server.

The record

CVE
CVE-2025-13321
Published
Dec 17, 2025
Updated
Dec 17, 2025
Vendor
Mattermost
Product
Mattermost
Classifications
CWE-532, T1005
Attack vector
local
Privileges
Unavailable

Timeline

How it unfolded

  1. Dec 17, 2025CVE publishedPublication date reported by the CVE source.
  2. Dec 17, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <=6.0.0

What conditions does exploitation require?

Attack vectorlocal
Required privilegesUnavailable in this record.

What is affected?

Mattermost · Mattermostversion=0 <=6.0.0

Published CVSS scores

3.3Mattermost, Inc.CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-532Insertion of Sensitive Information into Log File
T1005Data from Local System

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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