CVE-2024-8235 in Red Hat
Summary
by MITRE • 08/30/2024
A flaw was found in libvirt. A refactor of the code fetching the list of interfaces for multiple APIs introduced a corner case on platforms where allocating 0 bytes of memory results in a NULL pointer. This corner case would lead to a NULL-pointer dereference and subsequent crash of virtinterfaced. This issue could allow clients connecting to the read-only socket to crash the virtinterfaced daemon.
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Analysis
by VulDB Data Team • 08/02/2025
The vulnerability identified as CVE-2024-8235 resides within the libvirt virtualization management library, specifically affecting the virtinterfaced daemon responsible for interface management operations. This flaw represents a critical security issue that undermines the stability and availability of virtualization environments. The vulnerability stems from a code refactoring operation that altered how the system retrieves lists of network interfaces for various application programming interfaces. During this refactoring process, developers introduced a condition that fails to properly handle memory allocation scenarios where zero bytes are requested, creating a scenario that leads to unexpected system behavior. The issue manifests on platforms where the memory allocation function returns a NULL pointer when attempting to allocate zero bytes, a behavior that differs from typical memory management implementations across various operating systems. This specific edge case in memory handling creates a fundamental flaw in the daemon's operation that can be exploited by remote attackers.
The technical implementation of this vulnerability involves a NULL-pointer dereference condition that occurs when the virtinterfaced daemon attempts to process network interface information. When the refactored code encounters a situation where it must allocate memory for interface lists, and that allocation results in a NULL pointer due to zero-byte requests, subsequent operations attempt to dereference this NULL pointer. This dereference causes an immediate crash of the daemon process, resulting in a denial of service condition that affects all clients connected to the read-only socket interface. The daemon's failure to properly validate memory allocation outcomes during the interface enumeration process creates an exploitable condition that allows remote attackers to trigger the crash without requiring elevated privileges. The vulnerability specifically impacts the daemon's ability to handle multiple concurrent interface enumeration requests, making it particularly dangerous in high-traffic virtualization environments where interface management operations are frequent.
The operational impact of CVE-2024-8235 extends beyond simple service disruption to potentially compromise the integrity of virtualization infrastructure. When the virtinterfaced daemon crashes, it creates a cascading effect that can disrupt network connectivity for virtual machines managed by the libvirt system, as interface information becomes unavailable during the daemon's restart period. This vulnerability particularly affects environments where read-only socket access is enabled, as attackers can exploit this condition to repeatedly crash the daemon and maintain persistent disruption of service. The stability implications are severe since the daemon typically runs with elevated privileges to manage network interfaces, making successful exploitation potentially dangerous for the overall system security posture. Organizations using libvirt for virtual machine management face significant operational risk as this vulnerability can be exploited remotely, allowing attackers to perform denial-of-service attacks that can persist until the daemon is manually restarted or the system is rebooted.
Mitigation strategies for CVE-2024-8235 should focus on immediate patch deployment and operational hardening measures. The primary solution involves applying the vendor-provided security patches that correct the memory allocation handling in the libvirt codebase, specifically addressing the NULL-pointer dereference condition in the interface enumeration logic. System administrators should implement network segmentation to restrict access to the read-only socket interfaces where possible, reducing the attack surface for potential exploitation. Monitoring should be enhanced to detect repeated daemon crashes or abnormal interface enumeration patterns that may indicate exploitation attempts. Additionally, implementing process monitoring and automatic restart mechanisms for the virtinterfaced daemon can help maintain service availability while patches are deployed. Organizations should also consider implementing intrusion detection systems that can identify suspicious network traffic patterns associated with interface enumeration requests that could indicate attempted exploitation. The vulnerability aligns with CWE-476 which describes NULL pointer dereference conditions, and represents a potential ATT&CK technique under T1499 which covers network denial of service attacks. Regular security audits of virtualization management systems should include verification of memory handling code patterns to prevent similar refactoring-related issues from occurring in other components of the system.