VDB-379777 · CVE-2026-8075 · GCVE-0-2026-8075

Mattermost Desktop App up to 5.5.13/6.0.2.0/6.2.x denial of service

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
4.1	$0-$5k	2.22+

Summaryinfo

A vulnerability classified as problematic has been found in Mattermost Desktop App up to 5.5.13/6.0.2.0/6.2.x. This affects an unknown part. This manipulation causes denial of service. This vulnerability is tracked as CVE-2026-8075. The attack is possible to be carried out remotely. No exploit exists.

Detailsinfo

A vulnerability has been found in Mattermost Desktop App up to 5.5.13/6.0.2.0/6.2.x and classified as problematic. Affected by this vulnerability is some unknown processing. The manipulation with an unknown input leads to a denial of service vulnerability. The CWE definition for the vulnerability is CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. As an impact it is known to affect availability. The summary by CVE is:

Mattermost Desktop App versions <=6.2 5.5.13 6.0.2.0 fail to properly null check when checking for headers in the Mattermost Desktop App which allows any user to crash another channel members Desktop App via posting a malicious link with an embedded image that misses one of those headers. Mattermost Advisory ID: MMSA-2026-00668

The advisory is shared at mattermost.com. This vulnerability is known as CVE-2026-8075 since 05/07/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1499 for this issue.

Upgrading to version 5.13.6.0, 6.2.1.0 or 6.3.0 eliminates this vulnerability.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

Groupware Software

Vendor

Mattermost

Name

Desktop App

Version

License

open-source

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.3
VulDB Meta Temp Score: 4.1

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Denial of service
CWE: CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Upgrade: Desktop App 5.13.6.0/6.2.1.0/6.3.0

Timelineinfo

05/07/2026 CVE reserved
07/17/2026 +71 days Advisory disclosed
07/17/2026 +0 days VulDB entry created
07/17/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: mattermost.com
Status: Confirmed

CVE: CVE-2026-8075 (🔒)
GCVE (CVE): GCVE-0-2026-8075
GCVE (VulDB): GCVE-100-379777

Entryinfo

Created: 07/17/2026 12:35
Changes: 07/17/2026 12:35 (52)
Complete: 🔍
Cache ID: 216::103