CVE-2025-66630: GO-2026-4471 - Fiber has an insecure fallback in utils.UUIDv4() / utils.UUID() on crypto/rand failure in github.com/gofiber/fiber

CVE-2025-66630 · Severity: medium · CVSS 4 · Published 2026-02-19

Fiber has an insecure fallback in utils.UUIDv4() / utils.UUID() on crypto/rand failure in github.com/gofiber/fiber

Technologies: github.com/gofiber/fiber (Go), github.com/gofiber/fiber/v2 (Go). Vendors: Go.

Quick answers

Is CVE-2025-66630 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2025-66630 being exploited in the wild.
How severe is CVE-2025-66630?
Medium severity, with a CVSS score of 4, published 19 February 2026.
Which products and versions are affected?
github.com/gofiber/fiber (Go) SEMVER:introduced=0; github.com/gofiber/fiber/v2 (Go) SEMVER:introduced=0,fixed=2.52.11.
Is there a fix for CVE-2025-66630?
Yes. github.com/gofiber/fiber/v2 (Go): upgrade to 2.52.11 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
Am I affected by CVE-2025-66630?
Check whether you run github.com/gofiber/fiber (Go) or github.com/gofiber/fiber/v2 (Go) 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/gofiber/fiber/v2 (Go): upgrade to 2.52.11 or later
    go get github.com/gofiber/fiber/v2@v2.52.11

Affected products

  • github.com/gofiber/fiber (Go) SEMVER:introduced=0
  • github.com/gofiber/fiber/v2 (Go) SEMVER:introduced=0,fixed=2.52.11

Identifiers

  • CVE-2025-66630
  • GHSA-68rr-p4fp-j59v
  • GO-2026-4471

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