{"id":"CVE-2025-65849","aliases":[],"url":"https://o3.security/vulnerability/CVE-2025-65849","summary":"Altcha Proof-of-Work obfuscation mode cryptanalytic break","details":"A cryptanalytic break in Altcha Proof-of-Work obfuscation mode version 0.8.0 and later allows for remote visitors to recover the Proof-of-Work nonce in constant time via mathematical deduction.","published":"2025-12-08T21:30:22Z","modified":"2025-12-12T20:08:03.446058Z","cvss":null,"epss":{"score":0.00215,"percentile":0.11709,"asOf":"2026-08-24"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"npm","name":"altcha","fixedVersion":null}],"fix":null,"references":[{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-65849"},{"type":"WEB","url":"https://altcha.org/docs/v2/obfuscation"},{"type":"PACKAGE","url":"https://github.com/altcha-org/altcha"},{"type":"WEB","url":"https://github.com/altcha-org/altcha/blob/154f874cbcdd4e639783463130d13988a2bd1bdc/src/helpers.ts#L170-L194"},{"type":"WEB","url":"https://github.com/eternal-flame-AD/altcha-deobfs"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2025-12-12T20:08:03.446058Z"}}