Vulnerability in Gofiber Fiber
CVE-2026-44332
Fiber is an Express inspired web framework written in Go. Prior to 3.3.0, the default Authorizer function in the BasicAuth middleware in middleware/basicauth/config.go uses short-circuit evaluation that skips password hash comparison for non-existent usernames, enabling reliable remote username enumeration through response timing differences. This issue is fixed in version 3.3.0.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N.
EPSS exploit prediction
EPSS: 0.005 (42.1th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 42nd percentile — 42.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000
Affected products
- Gofiber Fiber — versions < 3.3.0
Weakness classification (CWE)
References
- github.com/gofiber/fiber/security/advisories/GHSA-g5vh-55hw-rxm8 (Exploit, Vendor Advisory)
- github.com/gofiber/fiber/pull/4245 (Patch, Issue Tracking)
- github.com/gofiber/fiber/commit/c7ac00edd19f9669b1aebbec6e229658baaa059e (Patch)
- github.com/gofiber/fiber/releases/tag/v3.3.0 (Release Notes)
Frequently asked questions
- What is CVE-2026-44332?
- CVE-2026-44332 is a medium-severity vulnerability in Gofiber Fiber, classified under Observable Discrepancy. CVSS score: 5.3/10. Published 2026-07-08.
- How severe is CVE-2026-44332?
- Medium severity. CVSS v3 base score is 5.3 out of 10.