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NVD / CVE Program· CNA Linux

CVE-2026-43085: netfilter: nfnetlink_log: initialize nfgenmsg in NLMSG_DONE terminator

MediumCVSS 5.5 · v3.1—No exploit Fix available

Noroxi assessment

Priority: Monitor (action score 22/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.12% (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 15d209bccf9273b4a8b4e579ba0e92d065b6ec8c, 1f3083aec8836213da441270cdb1ab612dd82cf4, 296f18e1c3a87c915a92ed27832d5040a22d1072.

Low priority for now. Upgrade to Linux Linux 15d209bccf9273b4a8b4e579ba0e92d065b6ec8c, 1f3083aec8836213da441270cdb1ab612dd82cf4, 296f18e1c3a87c915a92ed27832d5040a22d1072 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: netfilter: nfnetlink_log: initialize nfgenmsg in NLMSG_DONE terminator When batching multiple NFLOG messages (inst->qlen > 1), __nfulnl_send() appends an NLMSG_DONE terminator with sizeof(struct nfgenmsg) payload via nlmsg_put(), but never initializes the nfgenmsg bytes. The nlmsg_put() helper only zeroes alignment padding after the payload, not the payload itself, so four bytes of stale kernel heap data are leaked to userspace in the NLMSG_DONE message body. Use nfnl_msg_put() to build the NLMSG_DONE terminator, which initializes the nfgenmsg payload via nfnl_fill_hdr(), consistent with how __build_packet_message() already constructs NFULNL_MSG_PACKET headers.

Published
May 6, 2026
Updated
Nov 10, 2026
EPSS
0.1% · 2th 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
partial

Vulnrichment: CISA's decision-tree inputs.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

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  • when exploit code appears or is weaponized
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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

    • 2.6.23affected
    • 29c5d4afba51c71cfeadd3f74f3c42e064483fb0 and later · before 296f18e1c3a87c915a92ed27832d5040a22d1072affected · git
    • 29c5d4afba51c71cfeadd3f74f3c42e064483fb0 and later · before 9e2182865de781c41ab16b7985e9d26dcefea867affected · git
    • 29c5d4afba51c71cfeadd3f74f3c42e064483fb0 and later · before 57cc509d82b46150a11dcecc8b25eaa177eda34daffected · git
    • 29c5d4afba51c71cfeadd3f74f3c42e064483fb0 and later · before 368c22aea490f6f50df831b4f9e3623787686c5baffected · git
    • 29c5d4afba51c71cfeadd3f74f3c42e064483fb0 and later · before d1399632ba255d2e02c757af5d9f5d9279ce168caffected · git
    • 29c5d4afba51c71cfeadd3f74f3c42e064483fb0 and later · before d552bcfca323d175664d7444989b04f55666978aaffected · git
    • 29c5d4afba51c71cfeadd3f74f3c42e064483fb0 and later · before 15d209bccf9273b4a8b4e579ba0e92d065b6ec8caffected · git
    • 29c5d4afba51c71cfeadd3f74f3c42e064483fb0 and later · before 1f3083aec8836213da441270cdb1ab612dd82cf4affected · git
    • before 2.6.23not affected · semver
Affected versions · NVD (9)

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

  • linux linux kernel2.6.23.1 and later · before 5.10.258
  • linux linux kernel5.11 and later · before 5.15.209
  • linux linux kernel5.16 and later · before 6.1.175
  • linux linux kernel6.2 and later · before 6.6.136
  • linux linux kernel6.7 and later · before 6.12.83
  • linux linux kernel6.13 and later · before 6.18.24
  • linux linux kernel6.19 and later · before 6.19.14
  • linux linux kernel2.6.23
  • linux linux kernel7.0

Package-level exposure

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

EcosystemPackageAffected rangeFix
Debian:12linuxbefore 6.1.176-16.1.176-1
Debian:13linuxbefore 6.12.85-16.12.85-1
Debian:14linuxbefore 6.19.14-16.19.14-1
SUSE:Linux Micro 6.0kernel-defaultbefore 6.4.0-49.16.4.0-49.1
SUSE:Linux Micro 6.0kernel-kvmsmallbefore 6.4.0-49.16.4.0-49.1
SUSE:Linux Micro 6.0kernel-rtbefore 6.4.0-49.16.4.0-49.1
SUSE:Linux Micro 6.0kernel-sourcebefore 6.4.0-49.16.4.0-49.1
SUSE:Linux Micro 6.0kernel-source-rtbefore 6.4.0-49.16.4.0-49.1

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-2026-43083May 6, 2026 · net: ioam6: fix OOB and missing lock
    36Monitor
  • ← EarlierCVE-2026-43084May 6, 2026 · netfilter: nfnetlink_queue: make hash table per queue
    31Monitor
  • Later →CVE-2026-43088May 6, 2026 · net: af_key: zero aligned sockaddr tail in PF_KEY exports
    22Monitor

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 Linux15d209bccf9273b4a8b4e579ba0e92d065b6ec8cVendor (CNA)
Linux Linux1f3083aec8836213da441270cdb1ab612dd82cf4Vendor (CNA)
Linux Linux296f18e1c3a87c915a92ed27832d5040a22d1072Vendor (CNA)
Linux Linux368c22aea490f6f50df831b4f9e3623787686c5bVendor (CNA)
Linux Linux57cc509d82b46150a11dcecc8b25eaa177eda34dVendor (CNA)
Linux Linux9e2182865de781c41ab16b7985e9d26dcefea867Vendor (CNA)
Linux Linuxd1399632ba255d2e02c757af5d9f5d9279ce168cVendor (CNA)
Linux Linuxd552bcfca323d175664d7444989b04f55666978aVendor (CNA)
debian:linux6.1.176-1 · Debian:12Package registry (OSV)
suse:kernel-default6.4.0-49.1 · SUSE:Linux Micro 6.0Package registry (OSV)
suse:kernel-kvmsmall6.4.0-49.1 · SUSE:Linux Micro 6.0Package registry (OSV)
suse:kernel-rt6.4.0-49.1 · SUSE:Linux Micro 6.0Package registry (OSV)
suse:kernel-source6.4.0-49.1 · SUSE:Linux Micro 6.0Package registry (OSV)
suse:kernel-source-rt6.4.0-49.1 · SUSE:Linux Micro 6.0Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

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.

No dated events beyond publication.

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 (10 more)

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

All records