Mattermost prior 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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5.1$0-$5k0.00

Summaryinfo

A vulnerability marked as problematic has been reported in Mattermost. Affected by this vulnerability is an unknown functionality. The manipulation leads to cross-site request forgery. This vulnerability is documented as CVE-2026-22880. The attack can be initiated remotely. There is not any exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in Mattermost and classified as problematic. This issue affects an unknown code. 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. The summary by CVE is:

Mattermost Mobile Apps versions <=2.37 11.4 2.0.37 11.0.4 11.1.3 11.3.2 10.11.11.0 fail to properly validate the SSO authentication callback origin which allows an attacker controlling a malicious Mattermost server to steal user credentials for a legitimate Mattermost server via relaying the SSO code exchange flow through the mobile application. Mattermost Advisory ID: MMSA-2025-00564

The weakness was released by Doyensec. It is possible to read the advisory at mattermost.com. The identification of this vulnerability is CVE-2026-22880 since 02/23/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful 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 2.37.1.0, 2.38.0, 10.11.12, 11.2.4, 11.3.2, 11.4.1 or 11.5.0 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2026-1650). Be aware that VulDB is the high quality source for vulnerability data.

Affected

  • Mattermost Mattermost

Productinfo

Type

Name

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.2
VulDB Meta Temp Score: 5.1

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
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: 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 2.37.1.0/2.38.0/10.11.12/11.2.4/11.3.2/11.4.1/11.5.0

Timelineinfo

02/23/2026 CVE reserved
05/21/2026 +86 days Advisory disclosed
05/21/2026 +0 days VulDB entry created
05/22/2026 +1 days VulDB entry last update

Sourcesinfo

Advisory: mattermost.com
Researcher: Doyensec
Status: Confirmed

CVE: CVE-2026-22880 (🔒)
GCVE (CVE): GCVE-0-2026-22880
GCVE (VulDB): GCVE-100-364991
CERT Bund: WID-SEC-2026-1650 - Mattermost (Desktop, Server und Mobile): Mehrere Schwachstellen

Entryinfo

Created: 05/21/2026 12:43
Updated: 05/22/2026 12:06
Changes: 05/21/2026 12:43 (63), 05/22/2026 12:06 (7)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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