Description

CVE-2024-8176 is a stack overflow vulnerability within the libexpat library. It stems from the library's handling of recursive entity expansion when parsing XML documents. Deeply nested entity references can cause libexpat to recurse indefinitely, leading to stack exhaustion and a crash, potentially resulting in a denial-of-service (DoS). While its CVSS score is 7.5, the SOCRadar Vulnerability Risk Score (SVRS) of 73 suggests a significant risk level, nearing criticality. The presence of the "In The Wild" tag indicates that the vulnerability is actively exploited by hackers.

Key Insights

1. Recursive Entity Expansion: The root cause lies in the unchecked recursive nature of entity expansion within XML parsing performed by libexpat. Malicious actors can craft XML documents specifically designed to trigger this recursion.
2. Denial-of-Service Potential: The immediate and most likely impact is a denial-of-service (DoS) condition. By exhausting the stack, the application using libexpat becomes unavailable, impacting system uptime and service delivery.
3. Memory Corruption Risk: While less certain, the description indicates potential for exploitable memory corruption in some scenarios. This could enable attackers to gain control over the affected system, depending on how libexpat is used and the system's architecture.
4. Active Exploitation: The tag "In The Wild" demonstrates the vulnerability is actively exploited by hackers.

Mitigation Strategies

1. Update libexpat: Immediately update libexpat to the latest patched version. This is the primary and most effective mitigation, as patches address the vulnerable code.
2. Restrict XML Processing: Where feasible, limit or restrict the processing of XML documents from untrusted sources. Implement size limits on XML documents and disable or limit entity expansion.
3. Runtime Monitoring: Implement runtime monitoring to detect excessive stack usage by processes using libexpat. This can help identify and mitigate ongoing attacks before they fully exhaust system resources.
4. Web Application Firewall (WAF) Rules: Implement rules in Web Application Firewalls (WAFs) to detect and block malicious XML payloads designed to exploit this vulnerability.

Additional Information

If users have additional queries regarding this incident, they can use the 'Ask to Analyst' feature, contact SOCRadar directly, or open a support ticket for more information if necessary.