Mattermost Plugins up to 10.11.11/11.4.x Webhook Request unusual condition

CVSS Meta Temp Score
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CTI Interest Score
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2.2$0-$5k0.00

Summaryinfo

A vulnerability classified as problematic was found in Mattermost Plugins up to 10.11.11/11.4.x. This affects an unknown part of the component Webhook Request Handler. Such manipulation leads to unusual condition. This vulnerability is documented as CVE-2026-3109. The attack can be executed remotely. There is not any exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in Mattermost Plugins up to 10.11.11/11.4.x and classified as problematic. Affected by this issue is an unknown function of the component Webhook Request Handler. The manipulation with an unknown input leads to a unusual condition vulnerability. Using CWE to declare the problem leads to 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. Impacted is availability. CVE summarizes:

Mattermost Plugins versions <=11.4 10.11.11.0 fail to validate webhook request timestamps which allows an attacker to corrupt Zoom meeting state in Mattermost via replayed webhook requests. Mattermost Advisory ID: MMSA-2026-00584

The weakness was released by thecybertantrik. The advisory is shared for download at mattermost.com. This vulnerability is handled as CVE-2026-3109 since 02/24/2026. The exploitation is known to be difficult. The attack may be launched remotely. The exploitation needs additional levels of successful authentication. There are neither technical details nor an exploit publicly available.

Upgrading to version 10.11.12 or 11.5.0 eliminates this vulnerability.

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Productinfo

Type

Vendor

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 2.2
VulDB Meta Temp Score: 2.2

VulDB Base Score: 2.2
VulDB Temp Score: 2.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 2.2
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: Plugins 10.11.12/11.5.0

Timelineinfo

02/24/2026 CVE reserved
03/26/2026 +30 days Advisory disclosed
03/26/2026 +0 days VulDB entry created
06/08/2026 +74 days VulDB entry last update

Sourcesinfo

Advisory: mattermost.com
Researcher: thecybertantrik
Status: Confirmed

CVE: CVE-2026-3109 (🔒)
GCVE (CVE): GCVE-0-2026-3109
GCVE (VulDB): GCVE-100-353696

Entryinfo

Created: 03/26/2026 19:06
Updated: 06/08/2026 14:35
Changes: 03/26/2026 19:06 (65), 06/08/2026 14:35 (1)
Complete: 🔍
Cache ID: 216::103

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