CVE-2026-2454

highpriority · track · 34EPSS 0.003 · 20 %ileDEEURUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

0.29% (20th) EPSS

CVSS 8.6 · high

Is it mine?

26 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-23

Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to handle incorrectly reported array lengths which allows malicious user to cause OOM errors and crash the server via sending corrupted msgpack frames within websocket messages to calls plugin. Mattermost Advisory ID: MMSA-2025-00537

cvss

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

8.6

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5.8–8.6

v3.18.6highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 4

v3.15.8mediumAV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Lsecondary · FSTEC (BDU) RU

v3.15.8mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Lsecondary · ENISA EU

v3.15.8mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Lsecondary · responsibledisclosure@mattermost.comexploitability 3.9 · impact 1.4

v3.17.9highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)

ssvc

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

Exploitation: none · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-1287USCWE-1287US

affected products (26)

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 <2.3.1.0cert_bundDE
Mattermost Mattermost≤ Desktop <5.13.3.0cert_bundDE
Mattermost Mattermost≤ Desktop <5.13.4.0cert_bundDE
Mattermost Mattermost≤ Plugins <10.11.11cert_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≤ 11.2.0 ≤11.2.2enisa_euvdEU
Mattermost Mattermost≤ 11.3.0 ≤11.3.0enisa_euvdEU
Mattermost Mattermost≤ 10.11.0 ≤10.11.10enisa_euvdEU
Mattermost Inc Mattermost≤ 11.2.3fstec_bduRU

showing 20 of 26

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 CVE.org MITRE

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

references (4)

External citations — patches, advisories, analysis.

scry

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