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

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.

Published: 2025-10-13 Last update: 2026-06-17 Assigner: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2025-39965 is rated Low Risk (24.7/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.18%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2025-39965

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.02% 0.18% +0.16%
2 2025-10-14 — 0.02% —

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-39965

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.5 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.8 3.6 [email protected]

Weakness enumeration for CVE-2025-39965

OS Trackers for CVE-2025-39965

vendor priority summary link
debian unimportant CVE-2025-39965 unimportant priority: Debian including 1 source packages (linux), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2025-39965
redhat medium — https://access.redhat.com/security/cve/CVE-2025-39965
suse medium CVE-2025-39965 severity moderate: SUSE including 298 source package names (13.2-6.19:libjitterentropy3-3.4.1-3.1, 13.2-6.19:libopenssl3-3.1.4-6.1, …), 1155 product×package rows across 305 product lines (Container suse/sl-micro/6.0/baremetal-os-container, Container suse/sl-micro/6.0/base-os-container, … (305 product lines)): Fixed 1020, Known Not Affected 114, First Fixed 21. https://www.suse.com/security/cve/CVE-2025-39965/
ubuntu medium CVE-2025-39965 medium priority: Ubuntu including 157 source packages (linux, linux-allwinner-5.19, …), 1405 status rows across 9 suites (bionic, focal, jammy, noble, plucky, questing, trusty, upstream, xenial): DNE 1010, ignored 159, released 120, not-affected 112, needs-triage 2, pending 2. https://ubuntu.com/security/CVE-2025-39965

Affected software / configurations for CVE-2025-39965

Vendor Product Version Raw CPE
linux linux_kernel >= 6.6.103, < 6.6.109 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 6.12.43, < 6.12.50 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 6.15.11, < 6.16 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 6.16.2, < 6.16.10 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel 6.17 cpe:2.3:o:linux:linux_kernel:6.17:rc1:*:*:*:*:*:*
linux linux_kernel 6.17 cpe:2.3:o:linux:linux_kernel:6.17:rc2:*:*:*:*:*:*
linux linux_kernel 6.17 cpe:2.3:o:linux:linux_kernel:6.17:rc3:*:*:*:*:*:*
linux linux_kernel 6.17 cpe:2.3:o:linux:linux_kernel:6.17:rc4:*:*:*:*:*:*
linux linux_kernel 6.17 cpe:2.3:o:linux:linux_kernel:6.17:rc5:*:*:*:*:*:*
linux linux_kernel 6.17 cpe:2.3:o:linux:linux_kernel:6.17:rc6:*:*:*:*:*:*
linux linux_kernel 6.17 cpe:2.3:o:linux:linux_kernel:6.17:rc7:*:*:*:*:*:*

References for CVE-2025-39965

cvelogic Threat Intelligence