Vulnerability in proxychains-ng (DEBIAN-CVE-2025-34451)

Summary

Vulnerability in proxychains-ng (DEBIAN-CVE-2025-34451). Successful exploitation can lead to full system takeover. Mitigation: upgrade to 4.17-3.1 or later.

Original description

The description as published by the source.

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.

Source: OSV.dev (Open Source Vulnerabilities) OSV

Auto-generated summary

Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.

A vulnerability tracked as DEBIAN-CVE-2025-34451 has been found in proxychains-ng.
Successful exploitation can lead to full system takeover.
What to do: upgrade proxychains-ng to 4.17-3.1 or later.
If unsure, ask your IT team or search "proxychains-ng DEBIAN-CVE-2025-34451" on the vendor's site.

DEBIAN-CVE-2025-34451 (proxychains-ng)
Attack vector: local / unauthenticated
Patched: 4.17-3.1 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.

❓ What is the problem

A vulnerability (unclassified) exists in proxychains-ng.

📍 Affected scope

Check the vendor advisory for the affected versions of proxychains-ng.

🔥 Severity

Severity: ?. Successful exploitation can lead to full system takeover.

🔧 How to fix

Update to 4.17-3.1.

🛡️ Workaround

Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.

🔍 Detection

Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'proxychains-ng' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.

Response actions

Concrete steps and command examples for SOC/SRE teams to execute in order

1
Identify exposure identify
```
grep -r 'proxychains-ng' . | grep -v node_modules
```
リポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で proxychains-ng を grep し、稼働しているサービス・バージョンを把握する。
2
Apply patch patch
```
Upgrade proxychains-ng to 4.17-3.1
```
ステージング環境で 4.17-3.1 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
3
Post-deployment verification verify
```
Confirm patched version is live in production
```
パッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。

Affected packages

Debian:11 proxychains-ng

[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]

Debian:12 proxychains-ng

[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]

Debian:13 proxychains-ng

[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]

Debian:14 proxychains-ng

[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"4.17-3.1"}]}]

References

advisory security-tracker.debian.org