CVE-2025-58084Network attack vector

Application crash via malformed external URL

Published Oct 13, 2025 · Updated Oct 14, 2025

Improper URL validation in Mattermost Desktop App 5.13.0 and earlier allows remote authenticated users to crash the app via a malformed link. The client accepts a URL outside its configured Mattermost servers without validating its malformed structure before opening it. The attacker must have access to a configured server and persuade the user to click the link; the resulting impact is a client-process crash.

CVSS severity3.5
Low
EPSS probability0.30%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper URL validation in Mattermost Desktop App 5.13.0 and earlier allows remote authenticated users to crash the app via a malformed link. The client accepts a URL outside its configured Mattermost servers without validating its malformed structure before opening it. The attacker must have access to a configured server and persuade the user to click the link; the resulting impact is a client-process crash.

The record

CVE
CVE-2025-58084
Published
Oct 13, 2025
Updated
Oct 14, 2025
Vendor
Mattermost
Product
Mattermost
Classifications
CWE-1287, T1499
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Oct 13, 2025CVE publishedPublication date reported by the CVE source.
  2. Oct 14, 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 <=5.13.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Mattermost · Mattermostversion=0 <=5.13.0

Published CVSS scores

6.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
3.5Mattermost, Inc.CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:L

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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

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

Weakness, pattern, technique

CWE-1287Improper Validation of Specified Type of Input
T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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