CVE-2025-39965: linux kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: xfrm: xfrm_alloc_spi shouldn't use 0 as SPI x->id.spi == 0 means "no SPI assigned", but since commit 94f39804d891 ("xfrm: Duplicate SPI Handling"), we now create states and add them to the byspi list with this value. __xfrm_state_delete doesn't remove those states from the byspi list, since they shouldn't be there, and this shows up as a UAF the next time we go through the byspi list.
CVE-2025-39965CVSS 5.5Linux

CVE-2025-39965: linux kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: xfrm: xfrm_alloc_spi shouldn't use 0 as SPI x->id.spi == 0 means "no SPI assigned", but since commit 94f39804d891 ("xfrm: Duplicate SPI Handling"), we now create states and add them to the byspi list with this value. __xfrm_state_delete doesn't remove those states from the byspi list, since they shouldn't be there, and this shows up as a UAF the next time we go through the byspi list.

CVSS
5.5 MEDIUM
EPSS
7.37%
Known exploited
not in KEV
Product
linux kernel

What is known

In the Linux kernel, the following vulnerability has been resolved: xfrm: xfrm_alloc_spi shouldn't use 0 as SPI x->id.spi == 0 means "no SPI assigned", but since commit 94f39804d891 ("xfrm: Duplicate SPI Handling"), we now create states and add them to the byspi list with this value. __xfrm_state_delete doesn't remove those states from the byspi list, since they shouldn't be there, and this shows up as a UAF the next time we go through the byspi list.

Sources

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