CVE-2004-1453 in C Library
Summary
by MITRE
GNU glibc 2.3.4 before 2.3.4.20040619, 2.3.3 before 2.3.3.20040420, and 2.3.2 before 2.3.2-r10 does not restrict the use of LD_DEBUG for a setuid program, which allows local users to gain sensitive information, such as the list of symbols used by the program.
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Analysis
by VulDB Data Team • 06/01/2019
The vulnerability described in CVE-2004-1453 represents a significant security flaw in the GNU C Library (glibc) that affects multiple versions including 2.3.4 before 2.3.4.20040619, 2.3.3 before 2.3.3.20040420, and 2.3.2 before 2.3.2-r10. This issue specifically targets the LD_DEBUG environment variable functionality within setuid programs, creating an information disclosure vulnerability that can be exploited by local attackers to gain sensitive system information. The flaw stems from the improper restriction of debugging features that should normally be disabled or restricted in privileged contexts.
The technical implementation of this vulnerability lies in how glibc handles the LD_DEBUG environment variable when executing setuid programs. Normally, setuid programs run with elevated privileges and should have debugging features disabled to prevent potential information leakage that could aid attackers in understanding program behavior and identifying potential attack vectors. However, in the affected versions of glibc, the system failed to properly restrict LD_DEBUG usage even when programs were executing with elevated privileges. This means that local users could set the LD_DEBUG environment variable and observe detailed symbol information about setuid programs, effectively bypassing intended security boundaries. The information disclosed includes the list of symbols used by the program, which can reveal internal implementation details and potentially aid in crafting more sophisticated attacks against the target system.
From an operational impact perspective, this vulnerability enables local privilege escalation and reconnaissance capabilities that can significantly compromise system security. Attackers who gain access to a system can exploit this flaw to gather intelligence about setuid programs and their internal symbol tables, which can be used to identify potential weaknesses in program design or to craft targeted attacks against specific system components. The vulnerability is particularly concerning because it affects core system libraries that are fundamental to most Linux distributions and Unix-like systems. The information disclosure aspect creates a stealthy attack vector that doesn't necessarily trigger obvious system alerts while still providing attackers with valuable insights into system internals. This aligns with ATT&CK technique T1059.001 for executing system commands and T1068 for privilege escalation through local system manipulation.
The mitigation strategy for this vulnerability involves updating to the patched versions of glibc mentioned in the CVE description, specifically versions 2.3.4.20040619, 2.3.3.20040420, and 2.3.2-r10. System administrators should implement comprehensive patch management procedures to ensure all affected systems receive the necessary updates. Additionally, organizations should review their system configurations to ensure that debugging features are properly restricted in setuid contexts and implement monitoring for unusual LD_DEBUG usage patterns. The vulnerability is categorized under CWE-200 (Information Exposure) and represents a failure to properly restrict privileges in security-critical contexts. Regular security audits of system libraries and privilege management configurations should be conducted to prevent similar issues from arising in other components of the system infrastructure.