{"id":"CVE-2025-66506","revision":"2e3da367f8d249d7882d3ccf381a8773","records":[{"revision":"2e3da367f8d249d7882d3ccf381a8773","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2025-66506","aliases":[],"title":"Fulcio allocates excessive memory during token parsing","description":"Fulcio is a free-to-use certificate authority for issuing code signing certificates for an OpenID Connect (OIDC) identity. Prior to 1.8.3, function identity.extractIssuerURL splits (via a call to strings.Split) its argument (which is untrusted data) on periods. As a result, in the face of a malicious request with an (invalid) OIDC identity token in the payload containing many period characters, a call to extractIssuerURL incurs allocations to the tune of O(n) bytes (where n stands for the length of the function's argument), with a constant factor of about 16. This vulnerability is fixed in 1.8.3.","state":0,"publishedAt":"2025-12-04T22:04:41.637+00:00","modifiedAt":"2025-12-05T15:32:25.591+00:00","affected":[{"ecosystem":"Vendor product","name":"fulcio","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"sigstore\",\n                    \"product\": \"fulcio\",\n                    \"versions\": [\n                        {\n                            \"version\": \"< 1.8.3\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5,"severity":"HIGH"}],"references":["https://github.com/sigstore/fulcio/security/advisories/GHSA-f83f-xpx7-ffpw","https://github.com/sigstore/fulcio/commit/765a0e57608b9ef390e1eeeea8595b9054c63a5a"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2025-66506","license":"CVE Program Terms of Use","key":"cve-program:CVE-2025-66506","identifiers":["CVE-2025-66506"]},"retained":false,"historicalAffected":[]}],"coverage":[]}