Mattermost Desktop App up to 5.0.13 server unusual condition

CVSS Meta Temp Score
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CTI Interest Score
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4.5$0-$5k0.00

Summaryinfo

A vulnerability identified as problematic has been detected in Mattermost Desktop App up to 5.0.13. This issue affects some unknown processing of the component server Handler. Performing a manipulation results in unusual condition. This vulnerability is reported as CVE-2025-55035. The attack is possible to be carried out remotely. No exploit exists. You should upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as problematic, was found in Mattermost Desktop App up to 5.0.13. This affects some unknown functionality of the component server Handler. The manipulation with an unknown input leads to a unusual condition vulnerability. CWE is classifying the issue as CWE-754. The product does not check or incorrectly checks for unusual or exceptional conditions that are not expected to occur frequently during day to day operation of the product. This is going to have an impact on availability. The summary by CVE is:

Mattermost Desktop App versions <=5.13.0 fail to manage modals in the Mattermost Desktop App that stops a user with a server that uses basic authentication from accessing their server which allows an attacker that provides a malicious server to the user to deny use of the Desktop App via having the user configure the malicious server and forcing a modal popup that cannot be closed.

The weakness was disclosed by Doyensec. It is possible to read the advisory at mattermost.com. This vulnerability is uniquely identified as CVE-2025-55035 since 09/11/2025. The exploitability is told to be difficult. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. It demands that the victim is doing some kind of user interaction. The technical details are unknown and an exploit is not publicly available.

Upgrading to version 5.13.1.0 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2025-2056). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

  • Mattermost Mattermost

Productinfo

Type

Vendor

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.6
VulDB Meta Temp Score: 4.5

VulDB Base Score: 3.1
VulDB Temp Score: 3.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.1
CNA Vector (Mattermost): 🔒

CVSSv2info

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

Exploitinginfo

Class: Unusual condition
CWE: CWE-754
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Desktop App 5.13.1.0

Timelineinfo

09/11/2025 CVE reserved
10/16/2025 +35 days Advisory disclosed
10/16/2025 +0 days VulDB entry created
11/18/2025 +33 days VulDB entry last update

Sourcesinfo

Advisory: mattermost.com
Researcher: Doyensec
Status: Confirmed

CVE: CVE-2025-55035 (🔒)
GCVE (CVE): GCVE-0-2025-55035
GCVE (VulDB): GCVE-100-328827
CERT Bund: WID-SEC-2025-2056 - Mattermost Desktop: Schwachstellen erm&ouml;glichten Denial of Service

Entryinfo

Created: 10/16/2025 18:53
Updated: 11/18/2025 20:43
Changes: 10/16/2025 18:53 (65), 11/18/2025 20:43 (7)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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