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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2025-65849 Detail

Disputed     

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.”


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://altcha.org/docs/v2/obfuscation/ MITRE
https://github.com/altcha-org/altcha/blob/154f874cbcdd4e639783463130d13988a2bd1bdc/src/helpers.ts#L170-L194 MITRE
https://github.com/eternal-flame-AD/altcha-deobfs MITRE

Weakness Enumeration

CWE-ID CWE Name Source
CWE-327 Use of a Broken or Risky Cryptographic Algorithm CISA-ADP  

Change History

3 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2025-65849
NVD Published Date:
12/08/2025
NVD Last Modified:
12/11/2025
Source:
MITRE