CVE-2025-39965: xfrm: xfrm_alloc_spi shouldn't use 0 as SPI

Published Oct 13, 2025
·
Updated

In the Linux kernel, the following vulnerability has been resolved:

xfrm: xfrmallocspi 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.

xfrmstatedelete 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.

Affected Software

14 affected componentsFixes available
Linux Linux kernel
Microsoft azl3 kernel 6.6.104.2-1
Microsoft azl3 kernel 6.6.104.2-4
Linux Linux kernel>=6.6.103<6.6.109
Linux Linux kernel>=6.12.43<6.12.50
Linux Linux kernel>=6.15.11<6.16
Linux Linux kernel>=6.16.2<6.16.10
Linux Linux kernel=6.17-rc1
Linux Linux kernel=6.17-rc2
Linux Linux kernel=6.17-rc3
Linux Linux kernel=6.17-rc4
Linux Linux kernel=6.17-rc5
Linux Linux kernel=6.17-rc6
Linux Linux kernel=6.17-rc7

Event History

Oct 13, 2025
CVE Published
via MITRE·01:48 PM
Data Sourced
via MITRE·01:48 PM
DescriptionSeverity
Data Sourced
via NVD·02:15 PM
RemedyDescriptionSeverityAffected Software
Oct 15, 2025
Data Sourced
via Microsoft·01:01 AM
DescriptionSeverityWeakness
Data Sourced
via Microsoft·01:01 AM
Affected Software
Updated
via Microsoft·01:01 AM
DescriptionSeverity

Frequently Asked Questions

1

What is the severity of CVE-2025-39965?

CVE-2025-39965 has a severity rating that prompts users to assess their systems for potential security risks.

2

How do I fix CVE-2025-39965?

To fix CVE-2025-39965, update your Linux kernel to the latest patched version that addresses this vulnerability.

3

What systems are affected by CVE-2025-39965?

CVE-2025-39965 affects various versions of the Linux kernel where the xfrm functionality is implemented.

4

What is the impact of CVE-2025-39965?

The impact of CVE-2025-39965 may lead to security issues related to improper SPI handling in networking components.

5

When was CVE-2025-39965 reported?

CVE-2025-39965 was identified and reported following updates to the Linux kernel's xfrm component.

Contact

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