Is CVE-2026-27769 in the CISA KEV catalog?

No. CVE-2026-27769 is not currently on the CISA Known Exploited Vulnerabilities list.

What is the CVSS severity of CVE-2026-27769?

CVE-2026-27769 has a CVSS v3 base score of 2.7 (LOW).

What is the EPSS score for CVE-2026-27769?

CVE-2026-27769 has an EPSS score of 0.17% (6th percentile), estimating the probability of exploitation in the next 30 days.

How do I fix CVE-2026-27769?

Upgrade mattermost server to 10.11.13 or later.

CVE & CISA-KEV Catalog

CVE-2026-27769

LOW

2.7

CVSS v3

NVD

Description

Mattermost versions 10.11.x <= 10.11.12 fail to validate whether users were correctly owned by the correct Connected Workspace which allows a malicious remote server connected using the Conntexted Workspaces feature to change the displayed status of local users via the Connected Workspaces API.. Mattermost Advisory ID: MMSA-2026-00603

CWE-862Missing Authorization

How to fix

Remediation Available

mattermost serverNVD

Affected:>= 10.11.0, < 10.11.13Fixed in:10.11.13CVE-2026-27769derived from NVD

Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v3 Vector

Exploitability

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredHigh

User InteractionNone

ScopeUnchanged

Impact

ConfidentialityNone

IntegrityLow

AvailabilityNone

CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:N

Exploit Intelligence

0.17%probability of exploitation in 30 days

6thpercentile

Low risk: more likely to be exploited than 6% of all known CVEs.

References

Vendor Advisory1

mattermost.com

Related Vulnerabilities

Other CWE-862 (Missing Authorization) vulnerabilities, ordered by exploit likelihood. View all

CVE	Severity	CVSS	EPSS	Exploited	Fix
CVE-2021-39226	Critical	9.8	100%	KEV	Fix
CVE-2022-0543	Critical	10.0	100%	KEV	Fix
CVE-2021-21978	Critical	9.8	99%	-	Fix
CVE-2023-52163	High	8.8	96%	KEV	-
CVE-2022-1329	High	8.8	93%	-	-
CVE-2023-6875	Critical	9.8	90%	-	-

Embed a live status badge for CVE-2026-27769

Markdown

[![CVE-2026-27769](https://tridentstack.com/cve/badge/CVE-2026-27769.svg)](https://tridentstack.com/cve/CVE-2026-27769)

HTML

<a href="https://tridentstack.com/cve/CVE-2026-27769"><img src="https://tridentstack.com/cve/badge/CVE-2026-27769.svg" alt="CVE-2026-27769"></a>

Find and fix vulnerabilities across your fleet

TridentStack Control continuously scans your Windows, macOS, and Linux fleet for known vulnerabilities, prioritizes them by severity and active exploitation, and patches them automatically.

Start free

This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-04-22.