CVE-2025-65849

critical · 9.1

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.”

9.1

CVSS

0.2%

EPSS (exploit prob.)

13th

EPSS percentile

2025-12-08

Published

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Weaknesses

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

Query this programmatically:

curl https://evil-db.io/api/v1/cve/CVE-2025-65849