# CVE-2026-25882: GO-2026-4543 - Fiber has a Denial of Service Vulnerability via Route Parameter Overflow in github.com/gofiber/fiber

Source: https://junglewise.ai/threats/cve-2026-25882-fiber-has-a-denial-of-service-vulnerability-via-route-parameter  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-02-26  
License: CC BY 4.0 with a link back

CVE-2026-25882 · Severity: medium · CVSS 4 · Published 2026-02-26

Fiber has a Denial of Service Vulnerability via Route Parameter Overflow in github.com/gofiber/fiber

Technologies: [github.com/gofiber/fiber/v2 (Go)](https://junglewise.ai/threats/technologies/github-com-gofiber-fiber-v2), [github.com/gofiber/fiber/v3 (Go)](https://junglewise.ai/threats/technologies/github-com-gofiber-fiber-v3). Vendors: [Go](https://junglewise.ai/threats/vendors/go).

## Quick answers

**Is CVE-2026-25882 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-25882 being exploited in the wild.

**How severe is CVE-2026-25882?** Medium severity, with a CVSS score of 4, published 26 February 2026.

**Which products and versions are affected?** github.com/gofiber/fiber/v2 (Go) SEMVER:introduced=0,fixed=2.52.12; github.com/gofiber/fiber/v3 (Go) SEMVER:introduced=0,fixed=3.1.0.

**Is there a fix for CVE-2026-25882?** Yes. github.com/gofiber/fiber/v2 (Go): upgrade to 2.52.12 or later; github.com/gofiber/fiber/v3 (Go): upgrade to 3.1.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected by CVE-2026-25882?** Check whether you run github.com/gofiber/fiber/v2 (Go) or github.com/gofiber/fiber/v3 (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 2.52.12 or later

  ```sh
  go get github.com/gofiber/fiber/v2@v2.52.12
  ```

- github.com/gofiber/fiber/v3 (Go): upgrade to 3.1.0 or later

  ```sh
  go get github.com/gofiber/fiber/v3@v3.1.0
  ```


## Affected products

- github.com/gofiber/fiber/v2 (Go) SEMVER:introduced=0,fixed=2.52.12
- github.com/gofiber/fiber/v3 (Go) SEMVER:introduced=0,fixed=3.1.0

## Identifiers

- CVE-2026-25882
- GHSA-mrq8-rjmw-wpq3
- GO-2026-4543

## Related threats

- [Fiber CORS middleware wildcard domain bypass](https://junglewise.ai/threats/cve-2026-119285-fiber-is-an-express-inspired-web-framework-written-in-go-from-2)
- [Gofiber Fiber HSTS header omission in helmet middleware](https://junglewise.ai/threats/cve-2026-53624-gofiber-fiber-hsts-header-omission-in-helmet-middleware)
- [Gofiber Fiber IP spoofing in BalancerForward proxy helper](https://junglewise.ai/threats/cve-2026-45045-gofiber-fiber-ip-spoofing-in-balancerforward-proxy-helper)
- [Gofiber Fiber username enumeration in BasicAuth middleware](https://junglewise.ai/threats/cve-2026-44332-gofiber-fiber-username-enumeration-in-basicauth-middleware)
- [Go Fiber XSS in AutoFormat content negotiation](https://junglewise.ai/threats/cve-2026-42554-go-fiber-xss-in-autoformat-content-negotiation)