CVE-2023-54225: 
Linux Kernel vulnerability analysis and mitigation

CVE-2023-54225 is a vulnerability in the Linux kernel's IPA (IP Accelerator) subsystem, specifically in the net/ipa component. The flaw causes a transaction reference count underflow during modem shutdown when hashed filter/routing tables are incorrectly zeroed on hardware that does not support hashing. It affects the Linux kernel and was published on December 30, 2025. The CVSS severity is estimated as Medium (Feedly).

The root cause is an improper resource management issue (CWE-911 or related reference count mismanagement) in the IPA subsystem's GSI channel transaction handling. When the modem shuts down, ipa_filter_reset_table() allocates a transaction to zero modem filter table entries, including hashed table memory, even when hashing is not supported by the hardware. This results in an unused transaction being committed, which causes a reference count underflow. The fix prevents any attempt to clear hashed tables when hashing is not supported, eliminating the spurious unused transaction. Patches are available in the stable kernel tree at commits 50c24f0c9407, c00af3a818cc, and e11ec2b868af (Feedly, Kernel Git).

Exploitation of this vulnerability can lead to a reference count underflow in the Linux kernel's IPA subsystem, which may result in kernel instability or crashes (denial of service) during modem shutdown sequences. The impact is primarily an availability concern, as the underflow can cause unexpected kernel behavior on affected devices. There is no known confidentiality or integrity impact, and the vulnerability is not believed to enable privilege escalation or remote code execution (Feedly).

Apply the upstream Linux kernel patches that add a check to prevent zeroing hashed table memory when hashing is not supported. The relevant fixes are available in the stable kernel tree at commits 50c24f0c9407, c00af3a818cc, and e11ec2b868af. Users should update to a patched kernel version as provided by their Linux distribution. No configuration-based workaround is known; upgrading the kernel is the recommended remediation (Kernel Git).