CVE-2026-43452 json
netfilter: x_tables: guard option walkers against 1-byte tail reads
published 2026-05-08 6 mo ago modified 2026-10-19 20 d ago also EUVD-2026-28758
- cvss
- 8.2
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 45%
- public exploits
- 0
- none known
Summary
In the Linux kernel, the following vulnerability has been resolved:
netfilter: x_tables: guard option walkers against 1-byte tail reads
When the last byte of options is a non-single-byte option kind, walkers that advance with i += op[i + 1] ? : 1 can read op[i + 1] past the end of the option area.
Add an explicit i == optlen - 1 check before dereferencing op[i + 1] in xt_tcpudp and xt_dccp option walkers.
Patch / fix
- Linux Linux 5.10.253, 5.15.203, 6.1.167, 6.6.130, 6.12.78, 6.18.19, 6.19.9, 7.0
- linux Debian 12 6.1.170-1
- linux Debian 13 6.12.85-1
- linux Debian 14 6.19.10-1
debian advisories DEBIAN-CVE-2026-43452
- linux Ubuntu 22.04 LTS 5.15.0-186.196
- linux Ubuntu 24.04 LTS 6.8.0-136.136
- linux-aws Ubuntu 22.04 LTS 5.15.0-1112.119
- linux-aws Ubuntu 24.04 LTS 6.8.0-1061.64
- linux-gcp Ubuntu 22.04 LTS 5.15.0-1112.122
- linux-gcp Ubuntu 24.04 LTS 6.8.0-1064.72
- linux-gke Ubuntu 22.04 LTS 5.15.0-1108.114
- linux-gke Ubuntu 24.04 LTS 6.8.0-1059.67
ubuntu advisories UBUNTU-CVE-2026-43452
Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0
- kernel-source Linux Micro 6.1, Linux Micro 6.0 6.4.0-50.2
- kernel-default Linux Micro 6.1, Linux Micro 6.0 6.4.0-50.1
- kernel-kvmsmall Linux Micro 6.1, Linux Micro 6.0 6.4.0-50.1
- kernel-rt Linux Micro 6.1, Linux Micro 6.0 6.4.0-50.1
- kernel-source-rt Linux Micro 6.1, Linux Micro 6.0 6.4.0-50.2
- kernel-64kb SLE Module for Basesystem 15 SP7 6.4.0-150700.53.73.2
- kernel-syms SLE Module for Development Tools 15 SP7 6.4.0-150700.53.73.1
- kernel-azure SLE Module for Public Cloud 15 SP7 6.4.0-150700.53.73.2
suse advisories SUSE-SU-2026:3594-1SUSE-SU-2026:22810-1SUSE-SU-2026:22809-1SUSE-SU-2026:22904-1SUSE-SU-2026:22903-1SUSE-SU-2026:3166-1
- kernel-rt openSUSE Leap 16.0 6.12.0-160000.36.1
- dtb-aarch64 openSUSE Leap 16.0 6.12.0-160000.36.1
- kernel-64kb openSUSE Leap 16.0 6.12.0-160000.36.1
- kernel-syms openSUSE Leap 16.0 6.12.0-160000.36.1
- kernel-azure openSUSE Leap 16.0 6.12.0-160000.36.1
- kernel-obs-qa openSUSE Leap 16.0 6.12.0-160000.36.1
- kernel-source openSUSE Leap 16.0 6.12.0-160000.36.1
- kernel-default openSUSE Leap 16.0 6.12.0-160000.36.1
opensuse advisories openSUSE-SU-2026:21388-1
- git.kernel.org/stable/c/c2a445367a496a3c25dbc940c10c8bd1cfd4c14a commit
- git.kernel.org/stable/c/ae1e1267650638136b84c23f2b31250f0ccb6823 commit
- git.kernel.org/stable/c/c39f84e4be1be63fc60ca7141ea7b76edcea5907 commit
- git.kernel.org/stable/c/9b94f0e42ed248eb31929da84ed9f5310d7ff540 commit
- git.kernel.org/stable/c/5b18b8b35c7cded2d17b2b2604c9b0694ff48d1c commit
- git.kernel.org/stable/c/bc18551c6169eac5ed813778d3e3e484002dbbe5 commit
- git.kernel.org/stable/c/d04800323336eebf441d153f43234eac9b833d36 commit
- git.kernel.org/stable/c/cfe770220ac2dbd3e104c6b45094037455da81d4 commit
Vendor advisories
What the vendors themselves say about their products: affected, fixed or not affected, and what to do.
red hat product security vex CVE-2026-43452 updated cvss 5.5
kernel: netfilter: x_tables: guard option walkers against 1-byte tail reads
-
Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 moreaffected: no fix planned “Out of support scope”
-
Red Hat Enterprise Linux 7 perf, kernel, bpftool, kernel-rt, python-perf, kernel-kdump, +8 more Red Hat Enterprise Linux 8 perf, kernel, bpftool, kernel-rt, kernel-core, kernel-tools, +29 moreaffected: no fix available “Fix deferred”
-
Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +83 moreaffected: no fix available, no fix planned “Out of support scope”
-
Red Hat Enterprise Linux 10 kernelaffected: no fix available “Fix deferred”
Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf
CISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 24 d ago
Exploit prediction
0.54% chance of exploitation in the next 30 days, higher than 45% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 8.2 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H |
Affected products
- Linux Linux
Classification
- Weakness
-
- CWE-125 Out-of-bounds Read
- Technology feeds
References
-
git.kernel.org
/stable/c/c2a445367a496a3c25dbc940c10c8bd1cfd4c14a
patch
-
git.kernel.org
/stable/c/ae1e1267650638136b84c23f2b31250f0ccb6823
patch
-
git.kernel.org
/stable/c/c39f84e4be1be63fc60ca7141ea7b76edcea5907
patch
-
git.kernel.org
/stable/c/9b94f0e42ed248eb31929da84ed9f5310d7ff540
patch
-
git.kernel.org
/stable/c/5b18b8b35c7cded2d17b2b2604c9b0694ff48d1c
patch
-
git.kernel.org
/stable/c/bc18551c6169eac5ed813778d3e3e484002dbbe5
patch
-
git.kernel.org
/stable/c/d04800323336eebf441d153f43234eac9b833d36
patch
-
git.kernel.org
/stable/c/cfe770220ac2dbd3e104c6b45094037455da81d4
patch
Sources
- CVE List CVE-2026-43452
- NVD CVE-2026-43452
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