CVE-2026-1046

Arbitrary application execution via unvalidated server-controlled URLs in Help menu

MEDIUM
6.5
CVSS Score
Published: February 16, 2026 at 12:10 PM UTC
Updated: October 15, 2026 at 01:32 PM UTC
2 products affected across 1 vendorMattermost DesktopMattermost

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Severity
MEDIUM6.5
Exploit prediction
EPSS 0.3%
SSVC
No known exploit

Description

Mattermost Desktop App versions <=6.0 6.2.0 5.2.13.0 fail to validate help links which allows a malicious Mattermost server to execute arbitrary executables on a user’s system via the user clicking on certain items in the Help menu Mattermost Advisory ID: MMSA-2026-00577

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

5.13.0 ≤ v < 5.13.36.0.0 ≤ v < 6.0.3
0 ≤ v ≤ 5.2.130 ≤ v ≤ 6.2.0
Vendor states this is fixed in 5.13.3.0 (unaffected)
Vendor states this is fixed in 6.0.3.0 (unaffected)
Vendor states this is fixed in 6.1.0 (unaffected)

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

Patch and advisory references

References (1)

Vendor Advisory
Source: cverecord
https://mattermost.com/security-updates

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality
NONE
Integrity
HIGH
Availability
NONE
Vector?

Quick Info

StatusANALYZED
CWE
CWE-939

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