CVE-2023-52997 in Linux
Summary
by MITRE • 03/27/2025
In the Linux kernel, the following vulnerability has been resolved:
ipv4: prevent potential spectre v1 gadget in ip_metrics_convert()
if (!type) continue; if (type > RTAX_MAX) return -EINVAL; ... metrics[type - 1] = val;
@type being used as an array index, we need to prevent cpu speculation or risk leaking kernel memory content.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 12/07/2025
The vulnerability identified as CVE-2023-52997 resides within the Linux kernel's IPv4 networking subsystem, specifically in the ip_metrics_convert() function. This issue represents a speculative execution vulnerability that could potentially allow attackers to extract sensitive kernel memory contents through side-channel attacks. The flaw manifests when processing network metrics data where the variable type serves as an array index for the metrics array, creating a potential Spectre v1 vulnerability pattern that could be exploited by malicious actors.
The technical implementation of this vulnerability occurs in the ip_metrics_convert() function where the code processes network metrics data without proper bounds checking against speculative execution risks. When the type variable is used directly as an array index metrics[type - 1] = val, the kernel's CPU speculative execution mechanisms can potentially access memory locations that should remain protected. The conditional checks if (!type) continue; and if (type > RTAX_MAX) return -EINVAL; provide some validation but do not sufficiently protect against speculative execution attacks that can occur before these checks are fully evaluated by the processor. This creates a scenario where an attacker could potentially leverage CPU branch prediction and speculative execution to infer kernel memory contents through carefully crafted network metrics data.
The operational impact of CVE-2023-52997 extends beyond simple information disclosure, as it represents a fundamental security weakness in how the kernel handles network metrics processing. Attackers who can influence the type parameter through network packet manipulation could potentially extract kernel memory contents, including sensitive information such as cryptographic keys, network credentials, or other confidential data stored in kernel memory. This vulnerability affects systems running affected Linux kernel versions and could be particularly dangerous in environments where network traffic is not properly sanitized or where attackers have the ability to send crafted packets to the target system. The attack vector is primarily through network-based input processing, making it relevant to servers, routers, and any system processing network metrics data.
Mitigation strategies for CVE-2023-52997 focus on addressing the speculative execution vulnerability through kernel updates and code-level protections. The primary solution involves applying the patched kernel version that includes proper bounds checking and memory access controls to prevent the speculative execution attack pattern. Additionally, system administrators should implement network segmentation and access controls to limit exposure, while monitoring for unusual network traffic patterns that might indicate exploitation attempts. The fix typically involves ensuring that array indices are properly validated before speculative execution can occur, preventing the CPU from speculatively accessing memory locations that could leak kernel information. This vulnerability aligns with CWE-128 and ATT&CK techniques related to speculative execution attacks and information disclosure, emphasizing the need for comprehensive kernel security hardening measures.
This vulnerability demonstrates the critical importance of considering speculative execution attacks in kernel security design and highlights the ongoing challenge of protecting against sophisticated side-channel attack vectors that can bypass traditional security controls. The fix addresses a fundamental flaw in how kernel network metrics are processed and serves as a reminder of the need for continuous security auditing of kernel code, particularly in areas involving array indexing and memory access patterns that could be exploited through modern CPU architectural features.