VDB-348372 · CVE-2026-1628 · GCVE-0-2026-1628

Mattermost Desktop App up to 5.13.3 inclusion of functionality from untrusted control sphere

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.
5.3	$0-$5k	0.00

Summaryinfo

A vulnerability labeled as critical has been found in Mattermost Desktop App up to 5.13.3. This affects an unknown part. The manipulation results in inclusion of functionality from untrusted control sphere. This vulnerability is reported as CVE-2026-1628. The attack can be launched remotely. No exploit exists. The affected component should be upgraded.

Detailsinfo

A vulnerability classified as critical has been found in Mattermost Desktop App up to 5.13.3. Affected is an unknown part. The manipulation with an unknown input leads to a inclusion of functionality from untrusted control sphere vulnerability. CWE is classifying the issue as CWE-829. The product imports, requires, or includes executable functionality (such as a library) from a source that is outside of the intended control sphere. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

Mattermost Desktop App versions <=5.13.3 fail to attach listeners restricting navigation to external sites within the Mattermost app which allows a malicious server to expose preload script functionality to untrusted servers via having a user open an external link in their Mattermost server. Mattermost Advisory ID: MMSA-2026-00596

The weakness was disclosed by N and A. The advisory is shared for download at mattermost.com. This vulnerability is traded as CVE-2026-1628 since 01/29/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. There are neither technical details nor an exploit publicly available.

Upgrading to version 5.13.4.0 eliminates this vulnerability.

Once again VulDB remains the best source for 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: 5.4
VulDB Meta Temp Score: 5.3

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 4.6
CNA Vector (Mattermost): 🔒

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: Inclusion of functionality from untrusted control sphere
CWE: CWE-829
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

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: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Desktop App 5.13.4.0

Timelineinfo

01/29/2026 CVE reserved
03/02/2026 +32 days Advisory disclosed
03/02/2026 +0 days VulDB entry created
03/02/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: mattermost.com
Researcher: N, A
Status: Confirmed

CVE: CVE-2026-1628 (🔒)
GCVE (CVE): GCVE-0-2026-1628
GCVE (VulDB): GCVE-100-348372

Entryinfo

Created: 03/02/2026 16:41
Changes: 03/02/2026 16:41 (64)
Complete: 🔍
Cache ID: 216::103