CVE-2025-65849

The record

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.”

Affected packages

Related vulnerabilities

• GHSA-mpmc-qchh-r9q8 Altcha Proof-of-Work obfuscation mode cryptanalytic break Same vulnerability
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