Predictive Vulnerability Intelligence.

Product

  • Product
  • Pricing
  • Documentation

Company

  • About
  • Partnerships
  • Blog
  • Support

Legal

  • Terms
  • Privacy
  • Data Licensing

© 2026 FAUCET Technologies LLC. All rights reserved.

CVE-2026-3495

21
FAUCET Score

Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13 fail to escape some variables that could contain malicious content during error page composition which allows an attacker with access to edit some site configuration to execute some malicious code via injecting some JS as part of those values.. Mattermost Advisory ID: MMSA-2026-00622

First published: May 18, 2026Last modified: May 18, 2026

Impacted Technologies

VendorProductVersion(s)CPE
>= 10.11.0, < 10.11.14CPE matchmatch criteria
cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*
>= 11.5.0, < 11.5.2CPE matchmatch criteria
cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*
>= 10.11.0, <= 10.11.13CPE match
cpe:2.3:a:mattermost:mattermost:*:*:*:*:*:*:*:*
>= 11.5.0, <= 11.5.1CPE match
cpe:2.3:a:mattermost:mattermost:*:*:*:*:*:*:*:*

CVSS Data

CVSS version used by this source: 3.1

3.8LOW

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

Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
HIGH
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
LOW
Integrity Impact
LOW
Availability Impact
NONE
Exploitability Score
1.2
Impact Score
2.5
CvssVersion
3.1

Exploit Intelligence

EPSS Score
0.14%
Probability of exploitation in next 30 days
EPSS Percentile
4.0%
Percentile rank of EPSS score among Peer Group
As of 2026-07-27
Model: v2026.06.15
This CVE's current EPSS score of 0.0014 is in the 1st percentile among its peer group of 4,937 CVEs.

Social Chatter

The average CVE in this peer group has 0.0 Twitter, 0.0 Reddit, 0.0 Bluesky, 0.0 Mastodon, and 0.1 GitHub mentions.

Media Mentions

No media coverage found for this CVE.

The average CVE in this peer group has 0.0 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.

Remediation

Patch Available

Vendor Patches (4)

gopatch availablevia ghsa
Product: github.com/mattermost/mattermost/server/v8Fixed in: 10.11.14
gopatch availablevia ghsa
Product: github.com/mattermost/mattermost/server/v8Fixed in: 11.5.2
gopatch availablevia ghsa
Product: github.com/mattermost/mattermost/server/v8Fixed in: 8.0.0-20260310115442-5a1ea95044d
gopatch availablevia ghsa
Product: github.com/mattermost/mattermost-serverFixed in: 5.3.2-0.20260310115442-5a1ea95044dc

Vendor Advisories (1)

goGHSA-jx93-pf6x-874rlow

Mattermost doesn't escape some variables that could contain malicious content during error page composition

May 18, 2026

References

mattermost.com / security-updates
Vendor Advisory