CVE-2025-39965

CVE-2025-39965 is a medium-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Description

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.

Frequently asked questions

What is CVE-2025-39965?
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.
How severe is CVE-2025-39965?
CVE-2025-39965 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2025-39965 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (7th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-39965?
CVE-2025-39965 primarily affects Linux Linux Kernel. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-39965?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-39965 have an EU (EUVD) identifier?
Yes. CVE-2025-39965 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-34067.
When was CVE-2025-39965 published?
CVE-2025-39965 was published on 2025-10-13 and last updated on 2026-06-17.

References

Affected products (8)

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