CVE-2023-54231: 
Linux Ubuntu vulnerability analysis and mitigation

CVE-2023-54231 is a memory leak vulnerability in the Linux kernel's net/libwx networking subsystem, specifically in the wx_setup_rx_resources() function. When wx_alloc_page_pool() fails, the function does not release a previously allocated DMA buffer, resulting in a resource leak. The vulnerability affects Linux kernel versions starting from commit 850b971110b20cbcc2367516fefe78e84fec7d79 up to the fix commits in the 6.3.x and 6.4 stable series. It was published on December 30, 2025, with an EPSS score of approximately 0.024% (very low exploitation probability) and no CVSS base score has been assigned (Feedly, ENISA EUVD).

The root cause is a missing cleanup path in the wx_setup_rx_resources() function within the Linux kernel's libwx network driver library (CWE-401: Missing Release of Memory after Effective Lifetime). When wx_alloc_page_pool() returns an error, the function exits without calling dma_free_coherent() to release the DMA buffer that was allocated earlier in the same function. The fix adds a dma_free_coherent() call in the error path to properly release the DMA buffer. This is a local kernel resource management issue and is not remotely exploitable in the traditional sense (Feedly, ENISA EUVD).

The primary impact is a kernel memory leak in the DMA buffer allocation path of the libwx network driver, which could lead to resource exhaustion over time if the error condition is repeatedly triggered. This affects availability by potentially degrading system performance or causing denial-of-service conditions on systems using affected Wangxun network adapters. There is no known confidentiality or integrity impact, and no evidence of privilege escalation or lateral movement potential (Feedly).

The fix has been applied to the Linux kernel stable trees. Patches are available in commits 2371e1ecd445baf793a74db00ea6b2a2bc13c4c0 (for the 6.3.x stable branch, targeting patch version 6.3.2) and e315e7b83a22043bffee450437d7089ef373cbf6 (targeting the 6.4 release). Users should update to Linux kernel 6.3.2 or later, or 6.4 or later, to receive the fix. No configuration-based workaround is available; upgrading the kernel is the recommended remediation (ENISA EUVD, Kernel Git 6.3.x, Kernel Git 6.4).