2.6

CVE-2026-75588: mattermost

CVSS: 2.6v3.1LowAnalyzed
Published 17-09-2026Last modified 17-09-2026
Open JSON

Vulnerability summary

CVE-2026-75588 is a low (CVSS 2.6) vulnerability in mattermost. EPSS estimates a 0.22% chance of exploitation in the next 30 days, higher than 12.3% of scored vulnerabilities.

Overall risk
10/100
0100
Low · default modelHow is this calculated?
CVSS score
2.6/10
010
Low · v3.1 (CVE.org)
EPSS score
0.22%
0%100%
Low · +0.06 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 17-09-2026
    PublishedVulnerability first disclosed.
  2. 17-09-2026
    Last modifiedVulnerability information updated.

Description

Mattermost Desktop App versions <=6.2 6.2.2.0 fail to validate the URL scheme when checking whether a target URL is internal to the connected server, which allows a network-positioned attacker to load a plugin popout window over an insecure connection via a link using a downgraded URL scheme. Mattermost Advisory ID: MMSA-2026-00717

CVSS metrics

2 scores · 2 sources · 1 version

EPSS trend

Probability

0.22%

Chance of exploitation in the next 30 days

Percentile

12%

Versus all other CVEs

30-day change

+0.06 pp

From 0.17% on 21-09-2026

21-09-202621-10-2026
EPSS score
0.22%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Mattermost2 products

1 vendor · 2 products

References

1 links