CVE-2026-3471
published 2026-05-18CVE-2026-3471: Mattermost Desktop App versions <=6.1 6.0.1 5.4.13.0 fail to prevent an invalid URL from loading in a pop-up window in the Mattermost Desktop App which allows…
PriorityP429medium6.5CVSS 3.1
AVNACLPRNUIRSUCNINAH
EPSS
0.18%
8.2th percentile
Mattermost Desktop App versions <=6.1 6.0.1 5.4.13.0 fail to prevent an invalid URL from loading in a pop-up window in the Mattermost Desktop App which allows a malicious server owner to repeated crash the application via calling {{window.open('javascript:alert()');}}. Mattermost Advisory ID: MMSA-2026-00618
Affected
4 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| mattermost | mattermost | <= 6.0.1 | — |
| mattermost | mattermost_desktop | <= 5.4.13.0 | — |
| mattermost | mattermost_desktop | 6.0.0 – 6.0.1 | — |
| mattermost | mattermost_desktop | >= 6.1.0 < 6.2.0 | 6.2.0 |
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VulDB
Mattermost Desktop App up to 5.4.13/6.0.1/6.1.x improper authorization in handler for custom url scheme (EUVD-2026-30757)
vuldb·2026-05-18·CVSS 6.5
CVE-2026-3471 [MEDIUM] Mattermost Desktop App up to 5.4.13/6.0.1/6.1.x improper authorization in handler for custom url scheme (EUVD-2026-30757)
A vulnerability classified as problematic has been found in Mattermost Desktop App up to 5.4.13/6.0.1/6.1.x. This impacts an unknown function. Performing a manipulation results in improper authorization in handler for custom url scheme.
This vulnerability is identified as CVE-2026-3471. The attack can be initiated remotely. There is not any exploit available.
It is recommended to upgrade the affected component.
GHSA
GHSA-fhqj-97rr-gvhp: Mattermost Desktop App versions <=6
ghsa_unreviewed·2026-05-18
CVE-2026-3471 [MEDIUM] CWE-939 GHSA-fhqj-97rr-gvhp: Mattermost Desktop App versions <=6
Mattermost Desktop App versions <=6.1 6.0.1 5.4.13.0 fail to prevent an invalid URL from loading in a pop-up window in the Mattermost Desktop App which allows a malicious server owner to repeated crash the application via calling {{window.open('javascript:alert()');}}. Mattermost Advisory ID: MMSA-2026-00618
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2026-05-18
Published