CVE-2025-39965

Name of the Vulnerable Software and Affected Versions Linux Kernel (affected versions not specified)

Description The Linux kernel contains a flaw within the xfrm alloc spi() function in the net/xfrm/xfrm state.c module. Specifically, the function incorrectly handles Security Parameter Index (SPI) allocation, potentially leading to a use-after-free (UAF) condition. The issue arises because a commit introduced duplicate SPI handling, causing states to be added to the byspi list with a value of 0, which previously indicated no SPI was assigned. The xfrm state delete function does not remove these states from the byspi list, resulting in a UAF when the list is processed subsequently. This can lead to a denial-of-service condition.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.