Mattermost up to 10.11.12/11.3.2/11.4.2/11.5.0 cross-site request forgery

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.4$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as problematic, was found in Mattermost up to 10.11.12/11.3.2/11.4.2/11.5.0. The impacted element is an unknown function. Such manipulation leads to cross-site request forgery. This vulnerability is documented as CVE-2026-28741. The attack can be executed remotely. There is not any exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in Mattermost up to 10.11.12/11.3.2/11.4.2/11.5.0. Affected by this issue is some unknown functionality. The manipulation with an unknown input leads to a cross-site request forgery vulnerability. Using CWE to declare the problem leads to CWE-352. The web application does not, or can not, sufficiently verify whether a well-formed, valid, consistent request was intentionally provided by the user who submitted the request. Impacted is integrity. CVE summarizes:

Mattermost versions 10.11.x <= 10.11.12, 11.5.x <= 11.5.0, 11.4.x <= 11.4.2, 11.3.x <= 11.3.2 fail to validate CSRF tokens on an authentication endpoint which allows an attacker to update a user's authentication method via a CSRF attack by tricking a user into visiting a malicious page. Mattermost Advisory ID: MMSA-2026-00625

The weakness was released by Eva Sarafianou. The advisory is shared for download at mattermost.com. This vulnerability is handled as CVE-2026-28741 since 03/10/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. Successful exploitation requires user interaction by the victim. There are neither technical details nor an exploit publicly available.

Upgrading to version 10.11.13, 11.3.3, 11.4.3 or 11.5.1 eliminates this vulnerability.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.5
VulDB Meta Temp Score: 5.4

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

CNA Base Score: 6.8
CNA Vector (Mattermost): 🔒

CVSSv2info

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

Exploitinginfo

Class: Cross-site request forgery
CWE: CWE-352 / CWE-862 / CWE-863
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: Mattermost 10.11.13/11.3.3/11.4.3/11.5.1

Timelineinfo

03/10/2026 CVE reserved
04/15/2026 +35 days Advisory disclosed
04/15/2026 +0 days VulDB entry created
04/15/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: mattermost.com
Researcher: Eva Sarafianou
Status: Confirmed

CVE: CVE-2026-28741 (🔒)
GCVE (CVE): GCVE-0-2026-28741
GCVE (VulDB): GCVE-100-357716

Entryinfo

Created: 04/15/2026 14:03
Changes: 04/15/2026 14:03 (64)
Complete: 🔍
Cache ID: 216::103

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