CVE-2026-26230

lowpriority · track · 0OT risk · elevatedEPSS 0.002 · 6 %ileDEEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.17% (6th) EPSS

CVSS 3.8 · low

Is it mine?

20 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-27

Mattermost versions 10.11.x <= 10.11.10 fail to properly validate permission requirements in the team member roles API endpoint which allows team administrators to demote members to guest role. Mattermost Advisory ID: MMSA-2025-00531

cvss

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

3.8

010

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

v3.13.8lowAV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:Nsecondary · FSTEC (BDU) RU

v3.13.8lowCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:Nsecondary · ENISA EU

v3.13.8lowCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:Nsecondary · responsibledisclosure@mattermost.comexploitability 1.2 · impact 2.5

v3.13.5lowCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:N/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-284USCWE-863US

affected products (20)

Products and version ranges known to be affected.

Mattermost Mattermost Desktop <5.13.3.0all versionscert_bundDE
Mattermost Mattermost Desktop <5.13.4.0all versionscert_bundDE
Mattermost Mattermost Plugins <10.11.11all versionscert_bundDE
Mattermost Mattermost Plugins <2.3.1.0all versionscert_bundDE
Mattermost Mattermost Server <10.11.11all versionscert_bundDE
Mattermost Mattermost Server <11.2.3all versionscert_bundDE
Mattermost Mattermost Server <11.3.1all versionscert_bundDE
Mattermost Mattermost Server <11.4.0all versionscert_bundDE
Mattermost Mattermost≤ Plugins <10.11.11cert_bundDE
Mattermost Mattermost≤ Desktop <5.13.3.0cert_bundDE
Mattermost Mattermost≤ Desktop <5.13.4.0cert_bundDE
Mattermost Mattermost≤ Plugins <2.3.1.0cert_bundDE
Mattermost Mattermost≤ Server <10.11.11cert_bundDE
Mattermost Mattermost≤ Server <11.2.3cert_bundDE
Mattermost Mattermost≤ Server <11.3.1cert_bundDE
Mattermost Mattermost≤ Server <11.4.0cert_bundDE
Mattermost Mattermost≤ 10.11.0 ≤10.11.10enisa_euvdEU
Mattermost Inc Mattermost≤ 11.4.0fstec_bduRU
Mattermost Inc Mattermost≤ 10.11.11fstec_bduRU
mattermost mattermost server10.11.0 → 10.11.11nvdUScpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*

advisories (1)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2026-0422Mattermost: Mehrere SchwachstellenDeutsch2026-02-15csaf · cert_bundDE
Ein authentisierter Angreifer kann mehrere Schwachstellen in Mattermost ausnutzen, um falsche Informationen anzuzeigen, Informationen offenzulegen, Sicherheitskontrollen zu umgehen und eine Denial-of-Service-Situation zu erzeugen.

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu cert_bund nvd NVD CVE.org MITRE

published 2026-03-16modified 2026-06-17

references (4)

External citations — patches, advisories, analysis.

scry

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