CVE-2026-3473

highpriority · track · 28EPSS 0.001 · 4 %ileDEEURUUS
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
0.15% (4th) EPSS
CVSS 7.1 · high
Is it mine?
30 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 file ownership and access control, which allows an authenticated user to access and download files belonging to other users or teams via crafted Boards API requests using valid file IDs.. Mattermost Advisory ID: MMSA-2026-00620

01

cvss

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

7.1
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5.9–7.1

v3.17.1highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:Nprimary · NVD / NIST USexploitability 2.8 · impact 4.2
v3.17.1highAV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:Nsecondary · FSTEC (BDU) RU
v3.15.9mediumCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:L/A:Nsecondary · ENISA EU
v3.15.9mediumCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:L/A:Nsecondary · responsibledisclosure@mattermost.comexploitability 1.6 · impact 4.2
v3.17.1highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:Nsecondary · OSV
v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N/E:Usecondary · CVSS-BT (t0sche)
02

ssvc

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

Trackcoordinatorcisa_ssvcUS
03

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-639USCWE-639USCWE-639US
04

affected products (30)

Products and version ranges known to be affected.

showing 20 of 30
05

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-7pf2-9c95-w332Mattermost doesn't validate file ownership and access control2026-05-26ghsa · 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 file ownership and access control, which allows an authenticated user to access and download files belonging to other users or teams via crafted Boards API requests using valid file IDs. Mattermost Advisory ID: MMSA-2026-00620.

  • GO-2026-5817Mattermost doesn't validate file ownership and access control in github.com/mattermost/mattermost-server2026-07-07vendor · osvUS

    Mattermost doesn't validate file ownership and access control in github.com/mattermost/mattermost-server

06

also known as (7)

Other names and identifiers for this entity.

07

sources

Which sources assert this record, and when.

cnnvdenisa_euvdfstec_bduosvcert_bundnvdNVDCVE.orgMITRE
published 2026-05-22modified 2026-07-23
08

references (3)

External citations — patches, advisories, analysis.

scry

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