Source: secalert@redhat.com
The eglibc package before 2.14 incorrectly handled the getaddrinfo() function. An attacker could use this issue to cause a denial of service.
CVE-2013-4357 is a denial-of-service vulnerability in the getaddrinfo() function within eglibc versions prior to 2.14. This flaw allows attackers to trigger a system crash by crafting malicious network requests, rendering affected systems unavailable. Successful exploitation can lead to significant service disruption and potential data loss.
Step 1: Malicious Request Crafting: An attacker crafts a specially designed network request, likely a DNS query, that exploits a weakness in getaddrinfo()'s processing logic. This request is designed to trigger a specific error condition or resource exhaustion within the function.
Step 2: Request Submission: The attacker sends the malicious request to a vulnerable system, typically through a network service that uses getaddrinfo() (e.g., a web server, mail server, or any application that resolves hostnames).
Step 3: Function Execution: The vulnerable getaddrinfo() function processes the malicious request.
Step 4: Resource Exhaustion/Crash: Due to the crafted request, the function either exhausts system resources (e.g., memory, CPU) or encounters a critical error, leading to a denial-of-service condition. This could manifest as a system crash, process termination, or a complete inability to resolve hostnames, effectively rendering the system unusable.
The vulnerability lies within the getaddrinfo() function's handling of network address lookups. Specifically, the flaw involves incorrect error handling or resource allocation when processing malformed or crafted DNS requests. The root cause is likely related to how the function manages memory or internal data structures during the address resolution process. This can lead to a resource exhaustion condition, where the system is overwhelmed with requests, or a memory corruption issue, causing the program to crash. The exact nature of the flaw is not explicitly detailed in the provided information, but the description points to a problem in the function's internal logic, potentially a memory leak or an issue with how the function handles invalid input.
Due to the age of the vulnerability, it's likely that various threat actors, including both state-sponsored and financially motivated groups, have knowledge of and potentially exploit this vulnerability. The specific APTs or malware families that might leverage this are not explicitly known from the provided information. CISA KEV status is unlikely given the age of the vulnerability, but it's possible that systems with unpatched versions are targeted in opportunistic attacks.
Monitor network traffic for unusual DNS queries, especially those with malformed or unusual characteristics.
Analyze system logs for errors related to getaddrinfo() or DNS resolution failures.
Implement intrusion detection systems (IDS) with signatures that identify known exploit patterns.
Monitor system resource usage (CPU, memory, network) for sudden spikes or unusual behavior that could indicate a denial-of-service attack.
Review application logs for errors related to hostname resolution.
Upgrade to eglibc version 2.14 or later.
Apply security patches provided by the Linux distribution vendor.
Implement a web application firewall (WAF) to filter malicious requests.
Limit the number of DNS queries per second (QPS) to mitigate the impact of a denial-of-service attack.
Regularly scan systems for vulnerabilities and apply patches promptly.
Implement network segmentation to isolate vulnerable systems.