CVE-2023-28486 in sudo
Summary
by MITRE • 03/16/2023
Sudo before 1.9.13 does not escape control characters in log messages.
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Analysis
by VulDB Data Team • 05/21/2025
The vulnerability identified as CVE-2023-28486 affects sudo versions prior to 1.9.13 and represents a significant logging security flaw that can be exploited to manipulate or obscure audit trails within Unix-like systems. This issue specifically pertains to how sudo handles control characters in log messages, creating opportunities for malicious actors to interfere with system monitoring and forensic analysis. The vulnerability exists in the logging mechanism where control characters are not properly escaped, allowing attackers to inject special characters that can alter the appearance or interpretation of log entries.
Control characters in computing refer to non-printable characters that control how text is formatted or processed, including escape sequences, backspaces, and other terminal control codes. When these characters are not properly escaped in log messages, they can be interpreted by log viewers or parsing tools in unintended ways. This creates a vector for log manipulation where an attacker could potentially hide malicious activities by injecting control characters that alter the display or processing of log entries. The flaw is particularly concerning because sudo is a critical system component used extensively for privilege escalation, making it a prime target for exploitation.
The operational impact of this vulnerability extends beyond simple log obfuscation to potentially enable more sophisticated attacks that rely on compromising audit trails. Attackers could exploit this weakness to create false log entries, hide their activities from monitoring systems, or manipulate log analysis tools that rely on proper formatting of log messages. This vulnerability directly impacts the integrity of system security monitoring and can undermine the effectiveness of intrusion detection systems, security information and event management solutions, and forensic investigations. The flaw aligns with CWE-116, which describes improper encoding or escaping of control characters in output, and represents a form of log injection that can be classified under ATT&CK technique T1562.006 for "Impair Command History Logging".
Systems administrators and security professionals should prioritize updating sudo to version 1.9.13 or later to remediate this vulnerability, as the fix involves implementing proper escaping of control characters in log output. Organizations should also review their log management and monitoring configurations to ensure that log parsers and viewing tools can properly handle control characters without being affected by malicious injection. Additionally, implementing comprehensive monitoring of sudo usage and log integrity checks can help detect potential exploitation attempts. The vulnerability demonstrates the critical importance of proper input validation and output sanitization in security-critical components, particularly those involved in logging and auditing functions that are essential for maintaining system security posture and compliance requirements.