CVE-2024-0565 in Linux
Summary
by MITRE • 01/15/2024
An out-of-bounds memory read flaw was found in receive_encrypted_standard in fs/smb/client/smb2ops.c in the SMB Client sub-component in the Linux Kernel. This issue occurs due to integer underflow on the memcpy length, leading to a denial of service.
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 07/26/2025
The vulnerability identified as CVE-2024-0565 represents a critical out-of-bounds memory read flaw within the Linux kernel's SMB client implementation. This issue manifests in the receive_encrypted_standard function located in fs/smb/client/smb2ops.c, specifically affecting the SMB Client sub-component. The flaw arises from an integer underflow condition that occurs during memory copy operations, creating a scenario where the system attempts to read memory beyond the allocated bounds. Such vulnerabilities are particularly dangerous as they can lead to system instability and potential exploitation by malicious actors. The integer underflow condition in the memcpy length parameter creates a situation where the destination buffer receives data from an invalid memory location, potentially causing memory corruption or system crashes.
The technical execution of this vulnerability involves a specific sequence of operations within the SMB protocol handling code. When processing encrypted standard responses from SMB servers, the kernel's client implementation fails to properly validate the length parameter used in memory copy operations. This integer underflow condition causes the memcpy function to attempt reading from memory addresses that are either uninitialized, protected, or otherwise inaccessible. The flaw directly relates to CWE-129, which addresses improper validation of array indices, and CWE-191, which covers integer underflow conditions. These weaknesses in the kernel's SMB client implementation create a pathway for attackers to manipulate the memory copy operations and potentially trigger system-level issues.
The operational impact of CVE-2024-0565 extends beyond simple denial of service conditions, as the vulnerability can cause system instability and potential system crashes. When the integer underflow occurs during the memory copy operation, it can result in the kernel attempting to access memory regions that do not contain valid data, leading to segmentation faults or memory corruption. This vulnerability affects systems that utilize SMB client functionality, particularly those that connect to SMB servers or participate in SMB-based network communications. The impact is significant for enterprise environments where SMB protocol usage is prevalent, as it can disrupt file sharing services and potentially allow for more sophisticated attacks if exploited properly. From an ATT&CK perspective, this vulnerability aligns with techniques involving privilege escalation and denial of service, as it can be leveraged to compromise system availability and potentially gain further access to network resources.
Mitigation strategies for CVE-2024-0565 should prioritize immediate kernel updates from vendors such as Red Hat, Ubuntu, and other Linux distributions that have released patches addressing this specific integer underflow condition. System administrators should implement network segmentation to limit SMB client access to only necessary network segments and disable SMBv1 protocol support where possible. The patching process should include thorough testing in staging environments before deployment to production systems to ensure compatibility with existing SMB-based applications and services. Additional monitoring should be implemented to detect unusual network activity or system crashes that might indicate exploitation attempts. Organizations should also consider implementing intrusion detection systems that can identify patterns associated with SMB protocol exploitation attempts and maintain detailed logs of SMB client connections for forensic analysis. The vulnerability demonstrates the importance of proper input validation and memory management in kernel-level code, emphasizing the need for robust security practices in system-level programming and the critical role of regular security updates in maintaining system integrity.