CVE-2025-62690: GO-2025-4248 - Mattermost has missing redirect URL validation in github.com/mattermost/mattermost

CVE-2025-62690 · Severity: low · CVSS 3.1 · Published 2025-12-17

Mattermost versions 10.11.x <= 10.11.4 fail to validate redirect URLs on the /error page, which allows an attacker to redirect a victim to a malicious site via a crafted link opened in a new tab.

Technologies: github.com/mattermost/mattermost (Go), github.com/mattermost/mattermost-server (Go), github.com/mattermost/mattermost-server/v5 (Go), github.com/mattermost/mattermost-server/v6 (Go), github.com/mattermost/mattermost/server/v8 (Go), Mattermost Server. Vendors: Go, Mattermost.

Quick answers

Is CVE-2025-62690 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2025-62690 being exploited in the wild.
How severe is CVE-2025-62690?
Low severity, with a CVSS score of 3.1, published 17 December 2025.
Which products and versions are affected?
github.com/mattermost/mattermost (Go) SEMVER:introduced=10.11.0-rc1,fixed=10.11.5-0.20251016131338-dad6bd7a1509, SEMVER:introduced=10.11.0-rc1+incompatible,fixed=11.1.0+incompatible; github.com/mattermost/mattermost-server (Go) SEMVER:introduced=0; github.com/mattermost/mattermost-server/v5 (Go) SEMVER:introduced=0; github.com/mattermost/mattermost-server/v6 (Go) SEMVER:introduced=0; and 1 more.
Is there a fix for CVE-2025-62690?
Yes. github.com/mattermost/mattermost (Go): upgrade to 10.11.5-0.20251016131338-dad6bd7a1509, 11.1.0+incompatible or later; github.com/mattermost/mattermost/server/v8 (Go): upgrade to 8.0.0-20251016131338-dad6bd7a1509 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
Am I affected by CVE-2025-62690?
Check whether you run github.com/mattermost/mattermost (Go), github.com/mattermost/mattermost-server (Go), github.com/mattermost/mattermost-server/v5 (Go) or one of the others listed at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • github.com/mattermost/mattermost (Go): upgrade to 10.11.5-0.20251016131338-dad6bd7a1509, 11.1.0+incompatible or later
    go get github.com/mattermost/mattermost@v11.1.0+incompatible
  • github.com/mattermost/mattermost/server/v8 (Go): upgrade to 8.0.0-20251016131338-dad6bd7a1509 or later
    go get github.com/mattermost/mattermost/server/v8@v8.0.0-20251016131338-dad6bd7a1509

Affected products

  • github.com/mattermost/mattermost (Go) SEMVER:introduced=10.11.0-rc1,fixed=10.11.5-0.20251016131338-dad6bd7a1509, SEMVER:introduced=10.11.0-rc1+incompatible,fixed=11.1.0+incompatible
  • github.com/mattermost/mattermost-server (Go) SEMVER:introduced=0
  • github.com/mattermost/mattermost-server/v5 (Go) SEMVER:introduced=0
  • github.com/mattermost/mattermost-server/v6 (Go) SEMVER:introduced=0
  • github.com/mattermost/mattermost/server/v8 (Go) SEMVER:introduced=8.0.0-20250721062209-4952acea88ce,fixed=8.0.0-20251016131338-dad6bd7a1509
  • Mattermost Server

Identifiers

  • CVE-2025-62690
  • GHSA-q66g-q98c-q454
  • GO-2025-4248

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