Source: cve@mitre.org
In GNU Binutils 2.31.1, there is a use-after-free in the error function in elfcomm.c when called from the process_archive function in readelf.c via a crafted ELF file.
GNU Binutils 2.31.1 is vulnerable to a use-after-free vulnerability, allowing attackers to potentially execute arbitrary code. This flaw, triggered by a crafted ELF file, can lead to a crash or, in a worst-case scenario, complete system compromise. Successful exploitation requires the victim to process a malicious ELF file, making tools like readelf a primary target.
Step 1: Payload Delivery: The attacker crafts a malicious ELF file. This file is designed to exploit the vulnerability in readelf when it attempts to parse the file.
Step 2: Victim Interaction: The victim uses a vulnerable version of readelf (GNU Binutils 2.31.1) to process the malicious ELF file. This could be done directly by a user, or indirectly if readelf is used by another program or script.
Step 3: Triggering the Vulnerability: The readelf program calls process_archive to handle the archive file. The crafted ELF file's structure causes the error function to be called.
Step 4: Use-After-Free: The error function attempts to access memory that has already been freed, leading to the use-after-free condition.
Step 5: Exploitation (Potential): Depending on the system and the attacker's skill, this use-after-free could lead to a crash, information disclosure, or, in a more sophisticated attack, arbitrary code execution. The attacker could potentially control the freed memory and overwrite data, leading to control of the program's execution flow.
The vulnerability lies within the error function in elfcomm.c and is triggered when called from the process_archive function in readelf.c. The root cause is a use-after-free condition. Specifically, memory is freed prematurely, and then accessed later. The process_archive function handles archive files, and when parsing a crafted ELF file, it can trigger the error function. The error function, in turn, accesses memory that has already been freed, leading to the vulnerability. The specific flaw involves incorrect handling of memory management within the ELF parsing routines. The crafted ELF file likely manipulates the structure of the archive or its members to trigger the use of freed memory.
While no specific APTs are definitively linked to this specific CVE, the nature of the vulnerability (remote code execution potential) makes it attractive to various threat actors. Given the widespread use of GNU Binutils, it is likely that various actors, including those involved in supply chain attacks, would be interested. CISA KEV status: Not listed.
Monitor for unusual activity related to readelf or other tools that utilize GNU Binutils, especially when processing untrusted ELF files.
Analyze system logs for crashes or segmentation faults related to readelf or other related processes.
Implement file integrity monitoring to detect modifications to readelf or related binaries.
Network traffic analysis: Look for unusual network connections initiated by processes using readelf after processing ELF files, which could indicate command and control activity.
Examine core dumps generated after crashes for evidence of the use-after-free condition. This requires advanced forensic analysis.
Upgrade to a patched version of GNU Binutils (e.g., 2.31.1 or later) that addresses the vulnerability. This is the primary and most effective remediation step.
Restrict the use of readelf and other vulnerable tools to trusted users and environments. Limit exposure to untrusted ELF files.
Implement input validation to sanitize ELF files before processing them. This can help prevent the triggering of the vulnerability.
Employ a Web Application Firewall (WAF) to filter malicious requests.
Regularly update all software and operating systems to patch known vulnerabilities.