🛡️ CVE-2026-3471 — mattermost-desktop

How this vulnerability can be exploited

This issue can be reached over the network, attack complexity is low, an attacker needs no privileges on the target. A user must be tricked into taking some action. The scope is unchanged, so the impact stays within the vulnerable component. Rated impact: confidentiality none, integrity none, availability high.

CVSS metrics in full

The score comes from this vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

• Attack vector: Network — reachable from anywhere that can route to the service.
• Attack complexity: Low — the attack works reliably, with no preparation.
• Privileges required: None — an unauthenticated stranger can try it.
• User interaction: Required — someone has to click, open or visit something.
• Scope: Unchanged — the damage stays inside the vulnerable component.
• Confidentiality impact: None.
• Integrity impact: None.
• Availability impact: High — total loss, or loss the attacker controls.

Weakness class

CVE-2026-3471 is classified as CWE-939: Improper Authorization in Handler for Custom URL Scheme. The product uses a handler for a custom URL scheme, but it does not properly restrict which actors can invoke the handler using the scheme.

Affected software

CVE-2026-3471 is recorded against 1 package.

• mattermost-desktop (from 6.1.0 up to 6.2.0)

Timeline and source

Published on 18 May 2026 and last revised on 17 June 2026. No public exploit is currently recorded for this entry. Record sourced from NVD.

References

mattermost.com

Other advisories for this package

mattermost-desktop has other advisories on record. If you are patching this one, these are worth checking on the same host:

• CVE-2026-8075 (6.5 Medium, published 17 Jul 2026)
• CVE-2026-9602 (6.5 Medium, published 17 Jul 2026)
• CVE-2026-6517 (6.3 Medium, published 15 Jun 2026)
• CVE-2026-8683 (6.5 Medium, published 15 Jun 2026)
• CVE-2026-4643 (3.5 Low, published 18 May 2026)
• CVE-2026-1628 (4.6 Medium, published 2 Mar 2026)
• CVE-2026-1046 (7.6 High, published 16 Feb 2026)
• CVE-2025-13326 (3.9 Low, published 17 Dec 2025)

Same weakness in other software

These advisories are the same class of weakness (CWE-939: Improper Authorization in Handler for Custom URL Scheme) in other software:

• CVE-2026-21075 (published 10 Aug 2026)
• CVE-2026-21062 (3.3 Low, published 10 Aug 2026)
• CVE-2026-53408 (8.1 High, published 12 Jun 2026)
• CVE-2026-53407 (8.1 High, published 12 Jun 2026)
• CVE-2026-6445 (published 9 Jun 2026)
• CVE-2026-35394 (8.3 High, published 6 Apr 2026)
• CVE-2026-33335 (8.0 High, published 24 Mar 2026)
• CVE-2026-26123 (5.5 Medium, published 10 Mar 2026)

Details

Affected Packages

References