CVE-2026-66140

Description

A flaw was found in Exim. This vulnerability allows an attacker to perform directory traversal by mishandling arguments related to queue-name. This could enable unauthorized access to files outside of the designated spool area, potentially leading to a gain of privileges.

Statement

This Important flaw in Exim allows a local, unprivileged attacker to achieve privilege escalation through directory traversal. By exploiting mishandled queue-name arguments, an attacker can access sensitive files outside the intended spool area, increasing the risk of system compromise.

Mitigation

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.

Understanding the Weakness (CWE)

Integrity,Confidentiality,Availability

Technical Impact: Execute Unauthorized Code or Commands

The attacker may be able to create or overwrite critical files that are used to execute code, such as programs or libraries.

Integrity

Technical Impact: Modify Files or Directories

The attacker may be able to overwrite or create critical files, such as programs, libraries, or important data. If the targeted file is used for a security mechanism, then the attacker may be able to bypass that mechanism. For example, appending a new account at the end of a password file may allow an attacker to bypass authentication.

Confidentiality

Technical Impact: Read Files or Directories

The attacker may be able read the contents of unexpected files and expose sensitive data. If the targeted file is used for a security mechanism, then the attacker may be able to bypass that mechanism. For example, by reading a password file, the attacker could conduct brute force password guessing attacks in order to break into an account on the system.

Availability

Technical Impact: DoS: Crash, Exit, or Restart

The attacker may be able to overwrite, delete, or corrupt unexpected critical files such as programs, libraries, or important data. This may prevent the product from working at all and in the case of protection mechanisms such as authentication, it has the potential to lock out product users.

Frequently Asked Questions

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