CVE-2026-119285: Fiber · CORS wildcard origins matched without a dot boundary, allowing credentialed cross-origin reads
Affects github.com/gofiber/fiber/v2Source GCVE Database
Not known to be exploited · CVSS 5.9 Medium : upgrade to 2.52.3 when convenient.
Data as of 31 Oct 2026, 02:06 UTC
Thin evidence
One scorer or none| CNA (GitHub_M) | CVSS 3.1 | 5.9 |
|---|
- Patch
- Available – fixed in 2.52.3
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:L/A:NExploitation evidence
Disclosed: evidence found.
CVE published 29 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.
What to do
Upgrade github.com/gofiber/fiber/v2 to 2.52.3.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Gogithub.com/gofiber/fiber/v2 | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Upgrade Fiber to version 2.52.3 or later, where the CORS origin matching logic has been corrected to properly enforce dot boundaries and scheme checks. No other mitigation is required as the issue is fixed in these versions.
Description
A vulnerability in Fiber v2.52.1 and v2.52.2 CORS middleware allowed wildcard origins to be matched incorrectly without enforcing a dot boundary or scheme check. This caused origins with hosts ending in the base domain, but not actual subdomains (e.g., https://evil-example.com for https://*.example.com), to be reflected in Access-Control-Allow-Origin with credentials allowed. The issue was fixed in v2.52.3 by improving the origin matching logic.
References
- github.com/gofiber/fiber/security/advisories/GHSA-g5jq-qmqr-qrwf (opens in a new tab)
- nvd.nist.gov/vuln/detail/CVE-2026-119285 (opens in a new tab)
- github.com/gofiber/fiber/pull/2915 (opens in a new tab)
- github.com/gofiber/fiber/commit/1aac6f618b6bd3e159d2449acb4232a2170b976b (opens in a new tab)
- github.com/gofiber/fiber (opens in a new tab)
- github.com/gofiber/fiber/releases/tag/v2.52.3 (opens in a new tab)