{"cve":"CVE-2025-65849","nvd":{"published":"2025-12-08T19:15:50.817","modified":"2026-10-18T15:10:00.097","status":"Deferred","description":"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. NOTE: this is disputed by the Supplier because the product's objective is \"to discourage automated scraping / bots, not guarantee resistance to determined attackers.\" The documentation states “the goal is not to provide a secure cryptographic algorithm but to use a proof-of-work mechanism that allows any capable device to decrypt the hidden data.”","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","score":9.1},"cwes":["CWE-327"],"references":["https://altcha.org/docs/v2/obfuscation/","https://github.com/altcha-org/altcha/blob/154f874cbcdd4e639783463130d13988a2bd1bdc/src/helpers.ts#L170-L194","https://github.com/eternal-flame-AD/altcha-deobfs"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:16:40.427100871+00:00"},"epss":{"cve":"CVE-2025-65849","score":0.0022,"percentile":0.12417,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-mpmc-qchh-r9q8","url":"https://osv.dev/vulnerability/GHSA-mpmc-qchh-r9q8","summary":"Altcha Proof-of-Work obfuscation mode cryptanalytic break","modified":"2025-12-12T20:08:03.446058Z","packages":[{"ecosystem":"npm","name":"altcha","purl":"pkg:npm/altcha","ranges":[">=0.8.0 <=2.2.4"],"fixed":[]}]}],"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."]}