{"cve":"CVE-2025-66630","nvd":{"published":"2026-02-09T18:16:04.680","modified":"2026-06-17T09:57:08.067","status":"Analyzed","description":"Fiber is an Express inspired web framework written in Go. Before 2.52.11, on Go versions prior to 1.24, the underlying crypto/rand implementation can return an error if secure randomness cannot be obtained. Because no error is returned by the Fiber v2 UUID functions, application code may unknowingly rely on predictable, repeated, or low-entropy identifiers in security-critical pathways. This is especially impactful because many Fiber v2 middleware components (session middleware, CSRF, rate limiting, request-ID generation, etc.) default to using utils.UUIDv4(). This vulnerability is fixed in 2.52.11.","cvss_v4":{"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N","score":9.2},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L","score":9.4},"cwes":["CWE-338"],"references":["https://github.com/gofiber/fiber/commit/eb874b6f6c5896b968d9b0ab2b56ac7052cb0ee1","https://github.com/gofiber/fiber/releases/tag/v2.52.11","https://github.com/gofiber/fiber/security/advisories/GHSA-68rr-p4fp-j59v"],"products":["gofiber:fiber"],"source":"nvd","synced_at":"2026-10-19T22:22:27.261130201+00:00"},"epss":{"cve":"CVE-2025-66630","score":0.00535,"percentile":0.45154,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-68rr-p4fp-j59v","url":"https://osv.dev/vulnerability/GHSA-68rr-p4fp-j59v","summary":"Fiber has an insecure fallback in utils.UUIDv4() / utils.UUID() — predictable / zero‑UUID on crypto/rand failure","modified":"2026-09-10T03:49:54.322457183Z","packages":[{"ecosystem":"Go","name":"github.com/gofiber/fiber/v2","purl":"pkg:golang/github.com/gofiber/fiber/v2","ranges":["<2.52.11"],"fixed":["2.52.11"]}]},{"id":"GO-2026-4471","url":"https://osv.dev/vulnerability/GO-2026-4471","summary":"Fiber has an insecure fallback in utils.UUIDv4() / utils.UUID() on crypto/rand failure in github.com/gofiber/fiber","modified":"2026-02-19T20:41:19.007061Z","packages":[{"ecosystem":"Go","name":"github.com/gofiber/fiber","purl":"pkg:golang/github.com/gofiber/fiber","ranges":["all versions"],"fixed":[]},{"ecosystem":"Go","name":"github.com/gofiber/fiber/v2","purl":"pkg:golang/github.com/gofiber/fiber/v2","ranges":["<2.52.11"],"fixed":["2.52.11"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}