CVE-2023-54273 in Linux
Summary
by MITRE • 12/30/2025
In the Linux kernel, the following vulnerability has been resolved:
xfrm: Fix leak of dev tracker
At the stage of direction checks, the netdev reference tracker is already initialized, but released with wrong *_put() call.
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Analysis
by VulDB Data Team • 04/27/2026
The vulnerability CVE-2023-54273 represents a memory management issue within the Linux kernel's IPsec implementation, specifically affecting the XFRM subsystem responsible for packet transformation and security policy enforcement. This flaw manifests as a resource leak during the processing of network traffic through the kernel's security framework, where the netdev reference tracker fails to properly release network device references. The issue occurs during direction checks within the XFRM processing pipeline, indicating a critical failure in the kernel's resource lifecycle management for network interfaces used in security operations.
The technical root cause stems from improper reference counting mechanisms within the kernel's XFRM subsystem where the netdev reference tracker undergoes initialization but is subsequently released using an incorrect *_put() function call. This mismanagement results in network device references remaining allocated in memory even after they should be freed, creating a memory leak that accumulates over time. The flaw specifically impacts the kernel's ability to properly manage network device references during security policy enforcement operations, particularly when processing packets through the IPsec transformation framework. This improper resource handling directly violates fundamental kernel memory management principles and can lead to progressive memory consumption that ultimately impacts system stability and performance.
The operational impact of this vulnerability extends beyond simple memory consumption, potentially leading to system resource exhaustion and degraded performance in environments heavily utilizing IPsec security policies. Attackers could exploit this weakness to cause denial of service conditions by triggering the memory leak through repeated processing of security policy checks, eventually consuming available memory resources. The vulnerability affects systems running Linux kernels that implement the XFRM subsystem for IPsec functionality, particularly those utilizing network security policies that require direction checking operations. This weakness could be leveraged in sustained attack scenarios where adversaries continuously process traffic through security policies, amplifying the memory leak effect.
Mitigation strategies should prioritize immediate kernel updates to versions containing the patched implementation that correctly handles the netdev reference tracker release operations. System administrators should monitor memory usage patterns and implement proactive monitoring for unusual memory consumption that could indicate resource leak activity. The fix addresses the specific improper *_put() call issue by ensuring that network device references are properly released using the correct kernel reference counting functions. Organizations should also implement network traffic monitoring to detect abnormal patterns in IPsec policy processing that might indicate exploitation attempts. This vulnerability aligns with CWE-401, which categorizes improper resource release or cleanup issues, and represents a specific instance of improper reference counting that can lead to resource exhaustion. The ATT&CK framework would classify this as a resource exhaustion technique, potentially enabling denial of service conditions that could impact network availability and system stability.