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NVD / CVE Program· CNA Linux

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

MediumCVSS 5.5 · v3.1—Proof of concept Fix available

Noroxi assessment

Priority: Monitor (action score 22/100)

  • Public proof-of-concept code exists (GitHub); there is no record of exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.19% (FIRST EPSS).
  • Someone with local access to the system can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: Linux Linux 0baf92d0b1590b903c1f4ead75e61715e50e8146, 6.12.50, 6.16; azl3 kernel 6.6.104.2-4 on Azure Linux 3.0 6.6.112.1-1.
  • Severity is disputed: the assigning authority (CNA) scores it 7.8, NVD 5.5.

Low priority for now. Upgrade to Linux Linux 0baf92d0b1590b903c1f4ead75e61715e50e8146, 6.12.50, 6.16; azl3 kernel 6.6.104.2-4 on Azure Linux 3.0 6.6.112.1-1 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

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
Oct 13, 2025
Updated
Oct 30, 2026
EPSS
0.1% · 9th percentile
CWE
—

Report tools

JSON

Action score

22

Monitor

Low priority for now.

CVSS
22 / 40 · 5.5 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.1%

CISA SSVC decision

Exploitation
none
Automatable
no
Technical impact
total

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
5.5
CNA · Linux
7.8
2.3 point gap

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • Proof of concept exists, no weaponized module
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2025-39965

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
linuxlinux kernel

Versions reported by the vendor

Affected version ranges reported by the assigning authority (Linux). Independent of NVD's CPE analysis and usually ahead of it.

  • Linux Linux

    • fb58962aa3b9359988c7b5b15a971fd9ad5b0ecd, c67d4e7a8f90fb6361ca89d4d5c9a28f4e935e47affected
    • 3d8090bb53424432fa788fe9a49e8ceca74f0544 and later · before 0baf92d0b1590b903c1f4ead75e61715e50e8146affected · git
    • 2fc5b54368a1bf1d2d74b4d3b8eea5309a653e38 and later · before 9fcedabaae0096f712bbb4ccca6a8538af1cd1c8affected · git
    • 29e9158f91f99057dbd35db5e8674d93b38549fe and later · before a78e55776522373c446f18d5002a8de4b09e6bf7affected · git
    • 94f39804d891cffe4ce17737d295f3b195bc7299 and later · before cd8ae32e4e4652db55bce6b9c79267d8946765a9affected · git
    • 6.1.191 and later · before 6.2affected · semver
    • 6.15.11 and later · before 6.16affected · semver
    • 6.6.103 and later · before 6.6.109affected · semver
    • 6.12.43 and later · before 6.12.50affected · semver
    • 6.16.2 and later · before 6.16.10affected · semver
Affected versions · NVD (5)

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • linux linux kernel6.6.103 and later · before 6.6.109
  • linux linux kernel6.12.43 and later · before 6.12.50
  • linux linux kernel6.15.11 and later · before 6.16
  • linux linux kernel6.16.2 and later · before 6.16.10
  • linux linux kernel6.17

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Debian:13linuxbefore 6.12.57-16.12.57-1
Debian:14linuxbefore 6.16.10-16.16.10-1

Same product

linux: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-31431crypto: algif_aead - Revert to operating out-of-placeKEV
    90Now
  • CVE-2022-0847A flaw was found in the way the "flags" member of the new pipe buffer structure was lacking proper initialization in copy_page_to_iter_pipe…KEV
    89Now
  • CVE-2021-22555Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACEKEV
    85Now

Published before and after this one in the same product

  • ← EarlierCVE-2025-39963Oct 9, 2025 · io_uring: fix incorrect io_kiocb reference in io_link_skb
    31Monitor
  • ← EarlierCVE-2025-39964Oct 13, 2025 · crypto: af_alg - Disallow concurrent writes in af_alg_sendmsgKEV
    52Plan
  • Later →CVE-2025-39966Oct 15, 2025 · iommufd: Fix race during abort for file descriptors
    28Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
Linux Linux0baf92d0b1590b903c1f4ead75e61715e50e8146Vendor (CNA)
Linux Linux6.12.50Vendor (CNA)
Linux Linux6.16Vendor (CNA)
Linux Linux6.16.10Vendor (CNA)
Linux Linux6.2Vendor (CNA)
Linux Linux6.6.109Vendor (CNA)
Linux Linux9fcedabaae0096f712bbb4ccca6a8538af1cd1c8Vendor (CNA)
Linux Linuxa78e55776522373c446f18d5002a8de4b09e6bf7Vendor (CNA)
Linux Linuxcd8ae32e4e4652db55bce6b9c79267d8946765a9Vendor (CNA)
azl3 kernel 6.6.104.2-4 on Azure Linux 3.06.6.112.1-1 · CBL-Mariner ReleasesMicrosoft (MSRC)
debian:linux6.12.57-1 · Debian:13Package registry (OSV)

Exploit status

Proof of concept available

A public proof of concept or detection signature exists. Exploit knowledge is out there; don't delay patching.

Evidence

  • Proof-of-concept repository on GitHub ×1

Noroxi does not host or link to exploit code. Metasploit module names and Nuclei template ids are shown (names, not code); Exploit-DB entries and PoC repositories are given as counts only.

Public exploit evidence
SourceKindDate
Proof-of-concept repository on GitHubstars:102025-10-17

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

  1. Published
  2. First PoC+3 d
  3. TodayNov 12, 2026+395 d

Not on record for this CVE: EPSS history · patch commit or PR link · researcher credit · variant or chain candidate · public bounty program.

Technical details

Attack conditions

  • Someone with local access to the system can trigger it.
  • A low-privileged account is enough.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
none
Integrity
none
Availability
high · the service can be disrupted
Attack vector
Local
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality impact
None
Integrity impact
None
Availability impact
High

Weakness class (CWE)

—

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

nvd-primary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

References

Show all references (3 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records