CVE-2025-55073

mediumpriority · track · 21OT risk · elevatedEPSS 0.002 · 9 %ileDEEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.20% (9th) EPSS

CVSS 5.3 · medium

Is it mine?

28 products

Check your exposure

Who says so?

6 sources

cnnvd · enisa_euvd · fstec_bdu · osv

EPSS · scored 2026-10-27

Mattermost versions 10.11.x <= 10.11.3, 10.5.x <= 10.5.11, 10.12.x <= 10.12.0 fail to validate the relationship between the post being updated and the MSTeams plugin OAuth flow which allows an attacker to edit arbitrary posts via a crafted MSTeams plugin OAuth redirect URL.

cvss

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

5.4

010

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

v3.15.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:Nprimary · NVD / NIST USexploitability 3.9 · impact 1.4

v3.15.4mediumAV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:Lsecondary · FSTEC (BDU) RU

v3.15.4mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:Lsecondary · ENISA EU

v3.15.4mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:Lsecondary · responsibledisclosure@mattermost.comexploitability 2.8 · impact 2.5

v3.15.4mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:Lsecondary · OSV

v3.14.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/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-306USCWE-306USCWE-306US

affected products (28)

Products and version ranges known to be affected.

Mattermost Mattermost Mobile <2.33.0all versionscert_bundDE
Mattermost Mattermost Server <10.11.4all versionscert_bundDE
Mattermost Mattermost Server <10.12.1all versionscert_bundDE
Mattermost Mattermost Server <10.5.12all versionscert_bundDE
Mattermost Mattermost Server <11.0.0all versionscert_bundDE
Mattermost Mattermost≤ Server <10.11.4cert_bundDE
Mattermost Mattermost≤ Mobile <2.33.0cert_bundDE
Mattermost Mattermost≤ Server <10.12.1cert_bundDE
Mattermost Mattermost≤ Server <10.5.12cert_bundDE
Mattermost Mattermost≤ Server <11.0.0cert_bundDE
Mattermost Mattermost≤ 10.12.0 ≤10.12.0enisa_euvdEU
Mattermost Mattermost≤ 10.11.0 ≤10.11.3enisa_euvdEU
Mattermost Mattermost≤ 10.5.0 ≤10.5.11enisa_euvdEU
Mattermost Inc Mattermost10.11.0 → 10.11.3fstec_bduRU
Mattermost Inc Mattermost10.12 → 10.12.0fstec_bduRU
Mattermost Inc Mattermost10.5.0 → 10.5.11fstec_bduRU
mattermost mattermost server10.11.0 → 10.11.4nvdUScpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*
mattermost mattermost server10.12.0 → 10.12.1nvdUScpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*
mattermost mattermost server10.5.0 → 10.5.12nvdUScpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*
Go github.com/mattermost/mattermost-server10.11.0 → 10.11.4osvUSpkg:golang/github.com/mattermost/mattermost-server

showing 20 of 28

advisories (3)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2025-2315Mattermost Server und Mobile: Mehrere SchwachstellenDeutsch2025-10-15csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Mattermost Server und Mobile ausnutzen, um Informationen offenzulegen oder einen Denial of Service zu verursachen.
GHSA-ff85-qw3h-g9vpMattermost allows an attacker to edit arbitrary posts via a crafted MSTeams plugin OAuth redirect URL2025-11-14ghsa · osvUS
Mattermost versions 10.11.x <= 10.11.3, 10.5.x <= 10.5.11, 10.12.x <= 10.12.0 fail to validate the relationship between the post being updated and the MSTeams plugin OAuth flow which allows an attacker to edit arbitrary posts via a crafted MSTeams plugin OAuth redirect URL.
GO-2025-4129Mattermost allows an attacker to edit arbitrary posts via a crafted MSTeams plugin OAuth redirect URL in github.com/mattermost/mattermost-server2025-11-18vendor · osvUS
Mattermost allows an attacker to edit arbitrary posts via a crafted MSTeams plugin OAuth redirect URL in github.com/mattermost/mattermost-server

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 2025-11-14modified 2026-10-19

references (5)

External citations — patches, advisories, analysis.

scry

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