# CVE-2025-34451: proxychains-ng: rofl0r/proxychains-ng versions up to and including 4.17 and prior to commit cc005b7 contain a stack-based buffer over...

CVE-2025-34451 is fixed in 3 products on 1 platform, first by DEBIAN-CVE-2025-34451, released December 18, 2025. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2025-34451
- Priority: High
- CVSS: 7.8 (high)
- EPSS: 0.0027
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Dec 18, 2025

## Description

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.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | proxychains-ng Debian 14 | 4.17-3.1 | [DEBIAN-CVE-2025-34451](https://patchblox.com/security/data/fix/linux/debian-cve-2025-34451.md) | Dec 18, 2025 |
| Linux | proxychains-ng Fedora 43 | 4.17-8.fc43 | [FEDORA-2025-58FE871812](https://patchblox.com/security/data/fix/linux/fedora-2025-58fe871812.md) | Dec 28, 2025 |
| Linux | proxychains-ng-debuginfo Fedora 43 | 4.17-8.fc43 | [FEDORA-2025-58FE871812](https://patchblox.com/security/data/fix/linux/fedora-2025-58fe871812.md) | Dec 28, 2025 |
| Linux | proxychains-ng-debugsource Fedora 43 | 4.17-8.fc43 | [FEDORA-2025-58FE871812](https://patchblox.com/security/data/fix/linux/fedora-2025-58fe871812.md) | Dec 28, 2025 |

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