{"id":"CVE-2025-66565","title":"Fiber Utils is a collection of common functions created for Fiber","summary":"Fiber Utils is a collection of common functions created for Fiber. In versions 2.0.0-rc.3 and below, when the system's cryptographic random number generator (crypto/rand) fails, both functions silently fall back to returning predictable …","severity":"critical","cvss":9.8,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","cwe":["CWE-252","CWE-331","CWE-338","CWE-252","CWE-338"],"vendor":"gofiber","product":"utils","affected":["utils <= 1.2.0","utils = 2.0.0"],"published":"2025-12-09","updated":"2026-10-07","sourceUpdated":"2026-10-07T20:10:01.970","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2025-66565","references":[{"url":"https://github.com/gofiber/utils/commit/6c6cf047032b9c8dff43d29f990b4b10e9b02d47","label":"security-advisories@github.com"},{"url":"https://github.com/gofiber/utils/security/advisories/GHSA-m98w-cqp3-qcqr","label":"security-advisories@github.com"},{"url":"https://github.com/gofiber/utils/security/advisories/GHSA-m98w-cqp3-qcqr","label":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"tags":["nvd"],"epss":0.00468,"epssPercentile":0.38431,"ingestedAt":"2026-10-07T20:46:46.828Z","slug":"CVE-2025-66565","body":"## Overview\n\nFiber Utils is a collection of common functions created for Fiber. In versions 2.0.0-rc.3 and below, when the system's cryptographic random number generator (crypto/rand) fails, both functions silently fall back to returning predictable UUID values, including the zero UUID \"00000000-0000-0000-0000-000000000000\". The vulnerability occurs through two related but distinct failure paths, both ultimately caused by crypto/rand.Read() failures, compromising the security of all Fiber applications using these functions for security-critical operations. This issue is fixed in version 2.0.0-rc.4.\n\n## Affected\n\n- `utils <= 1.2.0`\n- `utils = 2.0.0`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"midnight","depthScore":54,"depthScoreParts":{"impact":53.9,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}