CVE-2024-54456 in Linux
Summary
by MITRE • 02/27/2025
In the Linux kernel, the following vulnerability has been resolved:
NFS: Fix potential buffer overflowin nfs_sysfs_link_rpc_client()
name is char[64] where the size of clnt->cl_program->name remains
unknown. Invoking strcat() directly will also lead to potential buffer overflow. Change them to strscpy() and strncat() to fix potential issues.
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Analysis
by VulDB Data Team • 05/24/2026
The vulnerability identified as CVE-2024-54456 resides within the Linux kernel's Network File System implementation, specifically affecting the nfs_sysfs_link_rpc_client() function. This issue represents a classic buffer overflow scenario that could potentially be exploited to compromise system integrity. The flaw manifests in the improper handling of string operations when linking RPC clients within the NFS subsystem, creating a pathway for malicious actors to manipulate memory structures.
The technical root cause stems from a direct concatenation operation using strcat() on a character array of fixed size 64 bytes. The variable name, which is a 64-byte buffer, receives data from clnt->cl_program->name without proper bounds checking. This approach violates fundamental security principles for string manipulation and creates a scenario where arbitrary data exceeding the buffer capacity can overwrite adjacent memory regions. The vulnerability falls under CWE-121, which addresses stack-based buffer overflow conditions, and more specifically aligns with CWE-787, representing out-of-bounds write vulnerabilities.
The operational impact of this vulnerability extends beyond simple memory corruption, potentially enabling privilege escalation attacks or system instability. When an attacker can control the data being written to the name buffer, they may manipulate the execution flow of the kernel, leading to unauthorized access to system resources or complete system compromise. The NFS subsystem's role in networked computing environments amplifies this risk, as the vulnerability could be exploited remotely through network-based NFS operations. This aligns with ATT&CK technique T1068, which covers local privilege escalation through kernel vulnerabilities, and T1566, covering the exploitation of network services.
The fix implemented addresses this vulnerability by replacing the unsafe strcat() function with strscpy() and strncat() operations. These functions provide proper bounds checking and prevent buffer overflows by limiting the number of characters copied to the destination buffer. The strscpy() function specifically ensures that the source string is copied safely without exceeding the destination buffer size, while strncat() provides controlled concatenation with explicit length parameters. This remediation approach follows the principle of least privilege and defensive programming practices, ensuring that all string operations within kernel space maintain memory safety. The solution also aligns with the principle of secure coding as outlined in the CERT Secure Coding Standards, particularly the STR02-C rule that mandates avoiding dangerous functions like strcat() in favor of safer alternatives. System administrators should prioritize applying this patch to all affected Linux kernel versions, as the vulnerability represents a critical security risk that could be exploited in both local and remote attack scenarios.