Mattermost up to 11.2.2/11.3.0 Playbook Run API authorization

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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4.2$0-$5k0.00

Summaryinfo

A vulnerability classified as problematic was found in Mattermost up to 11.2.2/11.3.0. Affected by this issue is some unknown functionality of the component Playbook Run API. The manipulation results in authorization. This vulnerability is known as CVE-2026-26304. It is possible to launch the attack remotely. No exploit is available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in Mattermost up to 11.2.2/11.3.0. It has been classified as problematic. Affected is an unknown function of the component Playbook Run API. The manipulation with an unknown input leads to a authorization vulnerability. CWE is classifying the issue as CWE-863. The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check. This allows attackers to bypass intended access restrictions. This is going to have an impact on integrity. CVE summarizes:

Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2 fail to verify run_create permission for empty playbookId, which allows team members to create unauthorized runs via the playbook run API. Mattermost Advisory ID: MMSA-2025-00542

The weakness was published by 0x7oda7123. The advisory is available at mattermost.com. This vulnerability is traded as CVE-2026-26304 since 02/13/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The technical details are unknown and an exploit is not available.

Upgrading to version 11.2.3, 11.3.1 or 11.4.0 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-12512). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.3
VulDB Meta Temp Score: 4.2

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

CNA Base Score: 4.3
CNA Vector (Mattermost): 🔒

CVSSv2info

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

Exploitinginfo

Class: Authorization
CWE: CWE-863 / CWE-285 / CWE-266
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 11.2.3/11.3.1/11.4.0

Timelineinfo

02/13/2026 CVE reserved
03/16/2026 +31 days Advisory disclosed
03/16/2026 +0 days VulDB entry created
03/21/2026 +5 days VulDB entry last update

Sourcesinfo

Advisory: mattermost.com
Researcher: 0x7oda7123
Status: Confirmed

CVE: CVE-2026-26304 (🔒)
GCVE (CVE): GCVE-0-2026-26304
GCVE (VulDB): GCVE-100-351330
EUVD: 🔒

Entryinfo

Created: 03/16/2026 22:28
Updated: 03/21/2026 16:36
Changes: 03/16/2026 22:28 (64), 03/17/2026 03:36 (1), 03/21/2026 16:36 (1)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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