CVE-2025-34451

Description

A flaw was found in proxychains-ng. An attacker can exploit a stack-based buffer overflow vulnerability in the proxy_from_string() function by providing crafted proxy configuration entries containing overly long username or password fields. This can lead to memory corruption or application crashes, resulting in a Denial of Service (DoS). Under specific conditions, this vulnerability could potentially be leveraged for further exploitation.

Statement

This vulnerability is rated Moderate for Red Hat as it can lead to a Denial of Service in proxychains-ng when processing crafted proxy configuration entries with overly long username or password fields. This component is available in Red Hat Community Projects (EPEL and Fedora) and requires an attacker to provide a malicious configuration file. Exploitation requires user interaction with a malicious configuration or a compromised configuration source.

Mitigation

Ensure that proxychains-ng configuration files are sourced only from trusted origins and are protected from unauthorized modification. If proxychains-ng is not essential for system operation, consider removing the package to eliminate the attack surface.

Understanding the Weakness (CWE)

CWE-121

Availability

Technical Impact: Modify Memory; DoS: Crash, Exit, or Restart; DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory)

Buffer overflows generally lead to crashes. Other attacks leading to lack of availability are possible, including putting the program into an infinite loop.

Integrity,Confidentiality,Availability,Access Control

Technical Impact: Modify Memory; Execute Unauthorized Code or Commands; Bypass Protection Mechanism

Buffer overflows often can be used to execute arbitrary code, which is usually outside the scope of a program's implicit security policy.

Integrity,Confidentiality,Availability,Access Control,Other

Technical Impact: Modify Memory; Execute Unauthorized Code or Commands; Bypass Protection Mechanism; Other

When the consequence is arbitrary code execution, this can often be used to subvert any other security service.

Frequently Asked Questions

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