CVE-2026-4646

mediumpriority · track · 0EPSS 0.003 · 16 %ileDEEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.25% (16th) EPSS

CVSS 4.3 · medium

Is it mine?

31 products

Check your exposure

Who says so?

6 sources

cnnvd · enisa_euvd · fstec_bdu · osv

EPSS · scored 2026-10-27

Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to validate user-supplied input in API request handlers which allows an authenticated attacker to crash the plugin process via a crafted HTTP request to the PR details endpoint.. Mattermost Advisory ID: MMSA-2026-00638

cvss

Technical severity, 0–10. One row per scoring source.

4.3

010

base score 0–10 · higher = more severe · hover a vector to decode

v3.14.3mediumAV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:Lsecondary · FSTEC (BDU) RU

v3.14.3mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:Lsecondary · ENISA EU

v3.14.3mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:Lsecondary · responsibledisclosure@mattermost.comexploitability 2.8 · impact 1.4

v3.14.3mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:Lsecondary · OSV

v3.14mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L/E:Usecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Trackcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-1287USCWE-1287USCWE-1287US

affected products (31)

Products and version ranges known to be affected.

Mattermost Mattermost <10.11.15all versionscert_bundDE
Mattermost Mattermost <11.4.5all versionscert_bundDE
Mattermost Mattermost <11.5.4all versionscert_bundDE
Mattermost Mattermost <11.6.1all versionscert_bundDE
Mattermost Mattermost <11.7.0all versionscert_bundDE
Mattermost Mattermost< 10.11.15cert_bundDE
Mattermost Mattermost< 11.4.5cert_bundDE
Mattermost Mattermost< 11.5.4cert_bundDE
Mattermost Mattermost< 11.6.1cert_bundDE
Mattermost Mattermost< 11.7.0cert_bundDE
Mattermost Mattermost≤ 10.11.0 ≤10.11.14enisa_euvdEU
Mattermost Mattermost≤ 11.6.0 ≤11.6.0enisa_euvdEU
Mattermost Mattermost≤ 11.4.0 ≤11.4.4enisa_euvdEU
Mattermost Mattermost≤ 11.5.0 ≤11.5.3enisa_euvdEU
Mattermost Inc Mattermost10.11.0 → 10.11.15fstec_bduRU
Mattermost Inc Mattermost11.4.0 → 11.4.5fstec_bduRU
Mattermost Inc Mattermost11.5.0 → 11.5.4fstec_bduRU
Mattermost Inc Mattermost11.6.0 → 11.6.1fstec_bduRU
mattermost mattermost server10.11.0 → 10.11.15nvdUScpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*
mattermost mattermost server11.4.0 → 11.4.5nvdUScpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*

showing 20 of 31

advisories (3)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2026-1243Mattermost: Mehrere Schwachstellen ermöglichen nicht spezifizierten AngriffDeutsch2026-04-22csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Mattermost ausnutzen, um einen nicht näher spezifizierten Angriff durchzuführen.
GHSA-rmvv-8v8w-rf7xMattermost doesn't validate user-supplied input in API request handlers2026-05-26ghsa · osvUS
Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to validate user-supplied input in API request handlers which allows an authenticated attacker to crash the plugin process via a crafted HTTP request to the PR details endpoint. Mattermost Advisory ID: MMSA-2026-00638
GO-2026-5833Mattermost doesn't validate user-supplied input in API request handlers in github.com/mattermost/mattermost-plugin-github2026-07-07vendor · osvUS
Mattermost doesn't validate user-supplied input in API request handlers in github.com/mattermost/mattermost-plugin-github

also known as (7)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu osv cert_bund nvd NVD CVE.org MITRE

published 2026-05-22modified 2026-07-23

references (3)

External citations — patches, advisories, analysis.

scry

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