Skip to content
Noroxi
NVD / CVE Program· CNA Linux

CVE-2026-52942: netfilter: nf_log: validate MAC header was set before dumping it

HighCVSS 7.1 · v3.1—No exploit Fix available

Noroxi assessment

Priority: Monitor (action score 28/100)

  • 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: 0.13% (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 2e96e1bc9b4d5450e6c33f078e19a9bc1dda6c0b, 65ef7397eb9a296e91839f5fd10be96f23d332e7, 8a81e336da685423f5b64aac4d571e63d674c52a; azl3 kernel 6.6.141.1-1 on Azure Linux 3.0 6.6.143.1-1.
  • Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Upgrade to Linux Linux 2e96e1bc9b4d5450e6c33f078e19a9bc1dda6c0b, 65ef7397eb9a296e91839f5fd10be96f23d332e7, 8a81e336da685423f5b64aac4d571e63d674c52a; azl3 kernel 6.6.141.1-1 on Azure Linux 3.0 6.6.143.1-1 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: netfilter: nf_log: validate MAC header was set before dumping it The fallback path of dump_mac_header() guards the MAC header access only with "skb->mac_header != skb->network_header", without checking skb_mac_header_was_set(). When the MAC header is unset, mac_header is 0xffff, so the test passes and skb_mac_header(skb) returns skb->head + 0xffff, ~64 KiB past the buffer; the loop then reads dev->hard_header_len bytes out of bounds into the kernel log. This is reachable via the netdev logger: nf_log_unknown_packet() calls dump_mac_header() unconditionally, and an skb sent through AF_PACKET with PACKET_QDISC_BYPASS reaches the egress hook with mac_header still unset (__dev_queue_xmit(), which would reset it, is bypassed). Add the skb_mac_header_was_set() check the ARPHRD_ETHER path already uses, and replace the open-coded MAC header length test with skb_mac_header_len(). Only skbs with an unset MAC header are affected; valid ones are dumped as before. BUG: KASAN: slab-out-of-bounds in dump_mac_header (net/netfilter/nf_log_syslog.c:831) Read of size 1 at addr ffff88800ea49d3f by task exploit/148 Call Trace: kasan_report (mm/kasan/report.c:595) dump_mac_header (net/netfilter/nf_log_syslog.c:831) nf_log_netdev_packet (net/netfilter/nf_log_syslog.c:938 net/netfilter/nf_log_syslog.c:963) nf_log_packet (net/netfilter/nf_log.c:260) nft_log_eval (net/netfilter/nft_log.c:60) nft_do_chain (net/netfilter/nf_tables_core.c:285) nft_do_chain_netdev (net/netfilter/nft_chain_filter.c:307) nf_hook_slow (net/netfilter/core.c:619) nf_hook_direct_egress (net/packet/af_packet.c:257) packet_xmit (net/packet/af_packet.c:280) packet_sendmsg (net/packet/af_packet.c:3114) __sys_sendto (net/socket.c:2265)

Published
Jun 24, 2026
Updated
Nov 10, 2026
EPSS
0.1% · 2th percentile

Report tools

JSON

Action score

28

Monitor

Low priority for now.

CVSS
28 / 40 · 7.1 / 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.

CNA vs NVD score

NVD
—
CNA · Linux
7.1
NVD has not scored this yet; the score shown is the CNA’s.

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
  • No public exploit code on record
  • A fix has been released

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

Follow CVE-2026-52942

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

One daily email digest (06:00 UTC); connect a webhook for KEV listings and weaponized exploits every 10 minutes on paid plans, on the hour on the free plan.

Your free account also gets you

  • CVE alerts: add the products and versions you run, get the new CVEs that affect them
  • Uptime monitoring: 1 site, instant email when it goes down
  • Add your domain: subdomains and takeover risk scanned every week (1 domain)
  • 10 scans an hour on the security tools, at most 30 a day (3 a day without an account), an API key and MCP
  • All your scans in one panel: findings, what changed in the last scan, a report per domain or per client (PDF, share link)
All free tools

Sign up with email · Have an account? Sign in

Free account, no card. Unfollow any time.

Don't want an account? Get "Exploited this week" by email every MondayDon't want an account? RSS feed for linux records
Is your version affected? Check it

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.

We use this product, ask for help

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

    • 2.6.36affected
    • 7eb9282cd0efac08b8377cbd5037ba297c77e3f7 and later · before 2e96e1bc9b4d5450e6c33f078e19a9bc1dda6c0baffected · git
    • 7eb9282cd0efac08b8377cbd5037ba297c77e3f7 and later · before d704ee9c7bc68a161684c51a7ac05b446dcf38d4affected · git
    • 7eb9282cd0efac08b8377cbd5037ba297c77e3f7 and later · before befb8968a2abdfa948d5600ea7f7a509a292a590affected · git
    • 7eb9282cd0efac08b8377cbd5037ba297c77e3f7 and later · before 8a81e336da685423f5b64aac4d571e63d674c52aaffected · git
    • 7eb9282cd0efac08b8377cbd5037ba297c77e3f7 and later · before c38d41134085193efd5b237cf513ad5b3421a60daffected · git
    • 7eb9282cd0efac08b8377cbd5037ba297c77e3f7 and later · before af1b7699466f6556b351fa25d3dc870abfb5d310affected · git
    • 7eb9282cd0efac08b8377cbd5037ba297c77e3f7 and later · before 65ef7397eb9a296e91839f5fd10be96f23d332e7affected · git
    • 7eb9282cd0efac08b8377cbd5037ba297c77e3f7 and later · before a84b6fedbc97078788be78dbdd7517d143ad1a77affected · git
    • before 2.6.36not affected · semver
Affected versions · NVD (7)

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

  • linux linux kernel2.6.36 and later · before 5.15.210
  • linux linux kernel5.16 and later · before 6.1.176
  • linux linux kernel6.2 and later · before 6.6.143
  • linux linux kernel6.7 and later · before 6.12.94
  • linux linux kernel6.13 and later · before 6.18.36
  • linux linux kernel6.19 and later · before 7.0.13
  • linux linux kernel7.1

Package-level exposure

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

EcosystemPackageAffected rangeFix
AlmaLinux:8bpftoolbefore 4.18.0-553.162.1.el8_104.18.0-553.162.1.el8_10
AlmaLinux:8kernelbefore 4.18.0-553.162.1.el8_104.18.0-553.162.1.el8_10
AlmaLinux:8kernel-abi-stablelistsbefore 4.18.0-553.162.1.el8_104.18.0-553.162.1.el8_10
AlmaLinux:8kernel-corebefore 4.18.0-553.162.1.el8_104.18.0-553.162.1.el8_10
AlmaLinux:8kernel-cross-headersbefore 4.18.0-553.162.1.el8_104.18.0-553.162.1.el8_10
AlmaLinux:8kernel-debugbefore 4.18.0-553.162.1.el8_104.18.0-553.162.1.el8_10
AlmaLinux:8kernel-debug-corebefore 4.18.0-553.162.1.el8_104.18.0-553.162.1.el8_10
AlmaLinux:8kernel-debug-develbefore 4.18.0-553.162.1.el8_104.18.0-553.162.1.el8_10
AlmaLinux:8kernel-debug-modulesbefore 4.18.0-553.162.1.el8_104.18.0-553.162.1.el8_10
AlmaLinux:8kernel-debug-modules-extrabefore 4.18.0-553.162.1.el8_104.18.0-553.162.1.el8_10
AlmaLinux:8kernel-develbefore 4.18.0-553.162.1.el8_104.18.0-553.162.1.el8_10
AlmaLinux:8kernel-docbefore 4.18.0-553.162.1.el8_104.18.0-553.162.1.el8_10
AlmaLinux:8kernel-headersbefore 4.18.0-553.162.1.el8_104.18.0-553.162.1.el8_10
AlmaLinux:8kernel-modulesbefore 4.18.0-553.162.1.el8_104.18.0-553.162.1.el8_10
AlmaLinux:8kernel-modules-extrabefore 4.18.0-553.162.1.el8_104.18.0-553.162.1.el8_10
AlmaLinux:8kernel-rtbefore 4.18.0-553.162.1.rt7.503.el8_104.18.0-553.162.1.rt7.503.el8_10
AlmaLinux:8kernel-rt-corebefore 4.18.0-553.162.1.rt7.503.el8_104.18.0-553.162.1.rt7.503.el8_10
AlmaLinux:8kernel-rt-debugbefore 4.18.0-553.162.1.rt7.503.el8_104.18.0-553.162.1.rt7.503.el8_10
AlmaLinux:8kernel-rt-debug-corebefore 4.18.0-553.162.1.rt7.503.el8_104.18.0-553.162.1.rt7.503.el8_10
AlmaLinux:8kernel-rt-debug-develbefore 4.18.0-553.162.1.rt7.503.el8_104.18.0-553.162.1.rt7.503.el8_10
AlmaLinux:8kernel-rt-debug-modulesbefore 4.18.0-553.162.1.rt7.503.el8_104.18.0-553.162.1.rt7.503.el8_10
AlmaLinux:8kernel-rt-debug-modules-extrabefore 4.18.0-553.162.1.rt7.503.el8_104.18.0-553.162.1.rt7.503.el8_10
AlmaLinux:8kernel-rt-develbefore 4.18.0-553.162.1.rt7.503.el8_104.18.0-553.162.1.rt7.503.el8_10
AlmaLinux:8kernel-rt-modulesbefore 4.18.0-553.162.1.rt7.503.el8_104.18.0-553.162.1.rt7.503.el8_10

+96

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-2026-52937Jun 24, 2026 · tap: fix stack info leak in tap_ioctl() SIOCGIFHWADDR
    22Monitor
  • ← EarlierCVE-2026-52941Jun 24, 2026 · net/smc: avoid NULL deref of conn->lnk in smc_msg_event tracepoint
    22Monitor
  • Later →CVE-2026-52943Jun 24, 2026 · net: skbuff: fix missing zerocopy reference in pskb_carve helpers
    31Monitor

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 Linux2e96e1bc9b4d5450e6c33f078e19a9bc1dda6c0bVendor (CNA)
Linux Linux65ef7397eb9a296e91839f5fd10be96f23d332e7Vendor (CNA)
Linux Linux8a81e336da685423f5b64aac4d571e63d674c52aVendor (CNA)
Linux Linuxa84b6fedbc97078788be78dbdd7517d143ad1a77Vendor (CNA)
Linux Linuxaf1b7699466f6556b351fa25d3dc870abfb5d310Vendor (CNA)
Linux Linuxbefb8968a2abdfa948d5600ea7f7a509a292a590Vendor (CNA)
Linux Linuxc38d41134085193efd5b237cf513ad5b3421a60dVendor (CNA)
Linux Linuxd704ee9c7bc68a161684c51a7ac05b446dcf38d4Vendor (CNA)
azl3 kernel 6.6.141.1-1 on Azure Linux 3.06.6.143.1-1 · CBL-Mariner ReleasesMicrosoft (MSRC)
almalinux:bpftool4.18.0-553.162.1.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel4.18.0-553.162.1.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt4.18.0-553.162.1.rt7.503.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-core4.18.0-553.162.1.rt7.503.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-debug4.18.0-553.162.1.rt7.503.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-debug-core4.18.0-553.162.1.rt7.503.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-debug-devel4.18.0-553.162.1.rt7.503.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-debug-modules4.18.0-553.162.1.rt7.503.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-debug-modules-extra4.18.0-553.162.1.rt7.503.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-devel4.18.0-553.162.1.rt7.503.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-modules4.18.0-553.162.1.rt7.503.el8_10 · AlmaLinux:8Package registry (OSV)
almalinux:kernel-rt-modules-extra4.18.0-553.162.1.rt7.503.el8_10 · AlmaLinux:8Package registry (OSV)
debian:linux6.1.176-1 · Debian:12Package registry (OSV)
red hat:kernel-rt0:4.18.0-553.162.1.rt7.503.el8_10 · Red Hat:enterprise_linux:8::nfvPackage registry (OSV)
red hat:kernel-rt-core0:4.18.0-553.162.1.rt7.503.el8_10 · Red Hat:enterprise_linux:8::nfvPackage registry (OSV)
red hat:kernel-rt-debug0:4.18.0-553.162.1.rt7.503.el8_10 · Red Hat:enterprise_linux:8::nfvPackage registry (OSV)
red hat:kernel-rt-debug-core0:4.18.0-553.162.1.rt7.503.el8_10 · Red Hat:enterprise_linux:8::nfvPackage registry (OSV)
red hat:kernel-rt-debug-debuginfo0:4.18.0-553.162.1.rt7.503.el8_10 · Red Hat:enterprise_linux:8::nfvPackage registry (OSV)
red hat:kernel-rt-debug-devel0:4.18.0-553.162.1.rt7.503.el8_10 · Red Hat:enterprise_linux:8::nfvPackage registry (OSV)
red hat:kernel-rt-debug-kvm0:4.18.0-553.162.1.rt7.503.el8_10 · Red Hat:enterprise_linux:8::nfvPackage registry (OSV)
red hat:kernel-rt-debug-modules0:4.18.0-553.162.1.rt7.503.el8_10 · Red Hat:enterprise_linux:8::nfvPackage registry (OSV)

+6

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.

National notice (Türkiye Cybersecurity Directorate / USOM)

Official security notices citing this record; remediation advice is on the agency's page.

All national notices →

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
high · data can be read
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
High
Integrity impact
None
Availability impact
High

Weakness class (CWE)

CWE-125 · Out-of-bounds Read

CVSS vector

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

nvd-secondary

Attack context

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

ATT&CK techniques

—

References

Show all references (10 more)

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

All records