Buffer overflow in Proxychains-Ng Project

CVE-2025-34451

rofl0r/proxychains-ng versions up to and including 4.17 and prior to commit cc005b7 contain a stack-based buffer overflow vulnerability in the function proxy_from_string() located in src/libproxychains.c. When parsing crafted proxy configuration entries containing overly long username or password fields, the application may write beyond the bounds of fixed-size stack buffers, leading to memory corruption or crashes. This vulnerability may allow denial of service and, under certain conditions, could be leveraged for further exploitation depending on the execution environment and applied mitigations.

Vulnerability class: Buffer Overflow

EPSS: 0.002 (13.6th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2025-34451?
CVE-2025-34451 is a high-severity vulnerability in Proxychains-Ng Project, classified under Stack-based Buffer Overflow. CVSS score: 7.8/10. Published 2025-12-18.
How severe is CVE-2025-34451?
High severity. CVSS v3 base score is 7.8 out of 10.