# CVE-2018-20744: GO-2023-1792 - Insecure wildcard CORS policy in github.com/rs/cors

Source: https://junglewise.ai/threats/cve-2018-20744-github-com-gofiber-fiber-v2-vulnerable-to-origin-validation-error  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2023-06-08  
License: CC BY 4.0 with a link back

CVE-2018-20744 · Severity: low · CVSS 3 · Published 2023-06-08

Insecure wildcard CORS policy in github.com/rs/cors

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

## Quick answers

**Is CVE-2018-20744 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2018-20744 being exploited in the wild.

**How severe is CVE-2018-20744?** Low severity, with a CVSS score of 3, published 8 June 2023.

**Which products and versions are affected?** github.com/gofiber/fiber/v2 (Go) SEMVER:introduced=2.0.0,fixed=2.43.0; github.com/rs/cors (Go) SEMVER:introduced=0,fixed=1.5.0.

**Is there a fix for CVE-2018-20744?** Yes. github.com/gofiber/fiber/v2 (Go): upgrade to 2.43.0 or later; github.com/rs/cors (Go): upgrade to 1.5.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected by CVE-2018-20744?** Check whether you run github.com/gofiber/fiber/v2 (Go) or github.com/rs/cors (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 2.43.0 or later

  ```sh
  go get github.com/gofiber/fiber/v2@v2.43.0
  ```

- github.com/rs/cors (Go): upgrade to 1.5.0 or later

  ```sh
  go get github.com/rs/cors@v1.5.0
  ```


## Affected products

- github.com/gofiber/fiber/v2 (Go) SEMVER:introduced=2.0.0,fixed=2.43.0
- github.com/rs/cors (Go) SEMVER:introduced=0,fixed=1.5.0

## Identifiers

- CVE-2018-20744
- GHSA-927h-x4qj-r242
- GO-2023-1792

## 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 IP spoofing in BalancerForward proxy helper](https://junglewise.ai/threats/cve-2026-45045-gofiber-fiber-ip-spoofing-in-balancerforward-proxy-helper)
- [Go Fiber XSS in AutoFormat content negotiation](https://junglewise.ai/threats/cve-2026-42554-go-fiber-xss-in-autoformat-content-negotiation)
- [GO-2026-4543 - Fiber has a Denial of Service Vulnerability via Route Parameter Overflow in github.com/gofiber/fiber](https://junglewise.ai/threats/cve-2026-25882-fiber-has-a-denial-of-service-vulnerability-via-route-parameter)
- [GO-2026-4471 - Fiber has an insecure fallback in utils.UUIDv4() / utils.UUID() on crypto/rand failure in github.com/gofiber/fiber](https://junglewise.ai/threats/cve-2025-66630-fiber-has-an-insecure-fallback-in-utils-uuidv4-utils-uuid)