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TI-2026-18668 Aliases CVE-2026-23231GHSA-gxm6-px42-mpjc

netfilter: nf_tables: fix use-after-free in nf_tables_addchain()

Priority LOW 38CWE-416Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 48 fixed, 1 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-416 and the CVSS impact.

Summary

In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: fix use-after-free in nf_tables_addchain() nf_tables_addchain() publishes the chain to table->chains via list_add_tail_rcu() (in nft_chain_add()) before registering hooks. If nf_tables_register_hook() then fails, the error path calls nft_chain_del() (list_del_rcu()) followed by nf_tables_chain_destroy() with no RCU grace period in between. This creates two use-after-free conditions: 1) Control-plane: nf_tables_dump_chains() traverses table->chains under rcu_read_lock(). A concurrent dump can still be walking the chain when the error path frees it. 2) Packet path: for NFPROTO_INET, nf_register_net_hook() briefly installs the IPv4 hook before IPv6 registration fails. Packets entering nft_do_chain() via the transient IPv4 hook can still be dereferencing chain->blob_gen_X when the error path frees the chain. Add synchronize_rcu() between nft_chain_del() and the chain destroy so that all RCU readers -- both dump threads and in-flight packet evaluation -- have finished before the chain is freed.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.01045 64th percentileScored 2026-11-07
Fix Partial Linux (Linux): 6.1.165, 6.6.128, 6.12.75 +3Red Hat: 17 advisoriesRed Hat: 48 fixed, 1 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux3.16 and later6.1.165, 6.6.128, 6.12.75, 6.18.14, 6.19.4, 7.0Patch availableCNA
  • Linux VendorLinux Affected 3.16 and later Fixed in 6.1.165, 6.6.128, 6.12.75, 6.18.14, 6.19.4, 7.0 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*3.16 to before 6.1.165; 6.2 to before 6.6.128; 6.7 to before 6.12.75; 6.13 to before 6.18.14; 6.19 to before 6.19.4VulnerableLinux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 3.16 to before 6.1.165; 6.2 to before 6.6.128; 6.7 to before 6.12.75; 6.13 to before 6.18.14; 6.19 to before 6.19.4 Vulnerable ·Linux

Remediation

  • Fix · CNA Linux (Linux) Fixed in 6.1.165, 6.6.128, 6.12.75, 6.18.14, 6.19.4, 7.0

Red Hat 17 advisories

  • RHSA-2026:10756 Released 2026-04-27 · Red Hat rating Moderate
    kernel-rt security update
    • Red Hat Enterprise Linux for Real Time (v. 7 ELS) kernel-rt-3.10.0-1160.148.1.rt56.1300.el7, kernel-rt-debug-3.10.0-1160.148.1.rt56.1300.el7, kernel-rt-debug-devel-3.10.0-1160.148.1.rt56.1300.el7 +4
  • RHSA-2026:10108 Released 2026-04-23 · Red Hat rating Important
    kernel security update
    • Red Hat CodeReady Linux Builder EUS (v.9.4) kernel-tools-libs-devel-5.14.0-427.121.1.el9_4, libperf-5.14.0-427.121.1.el9_4
    • Red Hat Enterprise Linux AppStream EUS (v.9.4) kernel-64k-debug-devel-5.14.0-427.121.1.el9_4, kernel-64k-debug-devel-matched-5.14.0-427.121.1.el9_4, kernel-64k-devel-5.14.0-427.121.1.el9_4 +11
    • Red Hat Enterprise Linux BaseOS EUS (v.9.4) bpftool-7.3.0-427.121.1.el9_4, kernel-5.14.0-427.121.1.el9_4, kernel-64k-5.14.0-427.121.1.el9_4 +29
    • Red Hat Enterprise Linux Real Time EUS (v.9.4) kernel-rt-5.14.0-427.121.1.el9_4, kernel-rt-core-5.14.0-427.121.1.el9_4, kernel-rt-debug-5.14.0-427.121.1.el9_4 +9
    • Red Hat Enterprise Linux Real Time for NFV EUS (v.9.4) kernel-rt-5.14.0-427.121.1.el9_4, kernel-rt-core-5.14.0-427.121.1.el9_4, kernel-rt-debug-5.14.0-427.121.1.el9_4 +11
  • RHSA-2026:9870 Released 2026-04-22 · Red Hat rating Moderate
    kernel security update
    • Red Hat Enterprise Linux Server (v. 7 ELS) bpftool-3.10.0-1160.148.1.el7, kernel-3.10.0-1160.148.1.el7, kernel-abi-whitelists-3.10.0-1160.148.1.el7 +11
    • Red Hat Enterprise Linux Server Optional (v. 7 ELS) kernel-debug-devel-3.10.0-1160.148.1.el7, kernel-tools-libs-devel-3.10.0-1160.148.1.el7
Show 14 more Red Hat advisories
  • RHSA-2026:9836 Released 2026-04-22 · Red Hat rating Moderate
    kernel security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.0) kernel-debug-devel-5.14.0-70.175.1.el9_0, kernel-debug-devel-matched-5.14.0-70.175.1.el9_0, kernel-devel-5.14.0-70.175.1.el9_0 +5
    • Red Hat Enterprise Linux BaseOS E4S (v.9.0) bpftool-5.14.0-70.175.1.el9_0, kernel-5.14.0-70.175.1.el9_0, kernel-abi-stablelists-5.14.0-70.175.1.el9_0 +14
  • RHSA-2026:9835 Released 2026-04-22 · Red Hat rating Moderate
    kernel-rt security update
    • Red Hat Enterprise Linux NFV E4S (v.9.0) kernel-rt-5.14.0-70.175.1.rt21.247.el9_0, kernel-rt-core-5.14.0-70.175.1.rt21.247.el9_0, kernel-rt-debug-5.14.0-70.175.1.rt21.247.el9_0 +9
    • Red Hat Enterprise Linux Real Time E4S (v.9.0) kernel-rt-5.14.0-70.175.1.rt21.247.el9_0, kernel-rt-core-5.14.0-70.175.1.rt21.247.el9_0, kernel-rt-debug-5.14.0-70.175.1.rt21.247.el9_0 +7
  • RHSA-2026:9644 Released 2026-04-22 · Red Hat rating Moderate
    kernel security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.2) kernel-64k-debug-devel-5.14.0-284.166.1.el9_2, kernel-64k-debug-devel-matched-5.14.0-284.166.1.el9_2, kernel-64k-devel-5.14.0-284.166.1.el9_2 +10
    • Red Hat Enterprise Linux BaseOS E4S (v.9.2) bpftool-7.0.0-284.166.1.el9_2, kernel-5.14.0-284.166.1.el9_2, kernel-64k-5.14.0-284.166.1.el9_2 +29
  • RHSA-2026:9643 Released 2026-04-22 · Red Hat rating Moderate
    kernel security update
    • Red Hat Enterprise Linux BaseOS AUS (v.8.4) bpftool-4.18.0-305.189.1.el8_4, kernel-4.18.0-305.189.1.el8_4, kernel-abi-stablelists-4.18.0-305.189.1.el8_4 +14
    • Red Hat Enterprise Linux BaseOS EUS EXTENSION (v.8.4) bpftool-4.18.0-305.189.1.el8_4, kernel-4.18.0-305.189.1.el8_4, kernel-abi-stablelists-4.18.0-305.189.1.el8_4 +14
  • RHSA-2026:9514 Released 2026-04-22 · Red Hat rating Moderate
    kernel security update
    • Red Hat Enterprise Linux BaseOS AUS (v.8.6) bpftool-4.18.0-372.188.1.el8_6, kernel-4.18.0-372.188.1.el8_6, kernel-abi-stablelists-4.18.0-372.188.1.el8_6 +14
    • Red Hat Enterprise Linux BaseOS E4S (v.8.6) bpftool-4.18.0-372.188.1.el8_6, kernel-4.18.0-372.188.1.el8_6, kernel-abi-stablelists-4.18.0-372.188.1.el8_6 +19
    • Red Hat Enterprise Linux BaseOS TUS (v.8.6) bpftool-4.18.0-372.188.1.el8_6, kernel-4.18.0-372.188.1.el8_6, kernel-abi-stablelists-4.18.0-372.188.1.el8_6 +14
  • RHSA-2026:9515 Released 2026-04-22 · Red Hat rating Moderate
    kernel security update
    • Red Hat Enterprise Linux BaseOS E4S (v.8.8) bpftool-4.18.0-477.136.1.el8_8, kernel-4.18.0-477.136.1.el8_8, kernel-abi-stablelists-4.18.0-477.136.1.el8_8 +14
    • Red Hat Enterprise Linux BaseOS TUS (v.8.8) bpftool-4.18.0-477.136.1.el8_8, kernel-4.18.0-477.136.1.el8_8, kernel-abi-stablelists-4.18.0-477.136.1.el8_8 +14
  • RHSA-2026:9512 Released 2026-04-22 · Red Hat rating Moderate
    kernel-rt security update
    • Red Hat Enterprise Linux Real Time E4S (v.9.2) kernel-rt-5.14.0-284.166.1.rt14.451.el9_2, kernel-rt-core-5.14.0-284.166.1.rt14.451.el9_2, kernel-rt-debug-5.14.0-284.166.1.rt14.451.el9_2 +9
    • Red Hat Enterprise Linux Real Time for NFV E4S (v.9.2) kernel-rt-5.14.0-284.166.1.rt14.451.el9_2, kernel-rt-core-5.14.0-284.166.1.rt14.451.el9_2, kernel-rt-debug-5.14.0-284.166.1.rt14.451.el9_2 +11
  • RHSA-2026:9513 Released 2026-04-22 · Red Hat rating Moderate
    kernel security update
    • Red Hat Enterprise Linux BaseOS AUS (v. 8.2) bpftool-4.18.0-193.195.1.el8_2, kernel-4.18.0-193.195.1.el8_2, kernel-abi-whitelists-4.18.0-193.195.1.el8_2 +14
  • RHSA-2026:9095 Released 2026-04-20 · Red Hat rating Moderate
    kernel security update
    • Red Hat Enterprise Linux AppStream EUS (v. 10.0) kernel-64k-debug-devel-6.12.0-55.69.1.el10_0, kernel-64k-debug-devel-matched-6.12.0-55.69.1.el10_0, kernel-64k-devel-6.12.0-55.69.1.el10_0 +12
    • Red Hat Enterprise Linux BaseOS EUS (v. 10.0) kernel-6.12.0-55.69.1.el10_0, kernel-64k-6.12.0-55.69.1.el10_0, kernel-64k-core-6.12.0-55.69.1.el10_0 +28
    • Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0) kernel-tools-libs-devel-6.12.0-55.69.1.el10_0, libperf-6.12.0-55.69.1.el10_0
    • Red Hat Enterprise Linux Real Time EUS (v. 10.0) kernel-rt-6.12.0-55.69.1.el10_0, kernel-rt-64k-6.12.0-55.69.1.el10_0, kernel-rt-64k-core-6.12.0-55.69.1.el10_0 +21
    • Red Hat Enterprise Linux Real Time for NFV EUS (v. 10.0) kernel-rt-6.12.0-55.69.1.el10_0, kernel-rt-core-6.12.0-55.69.1.el10_0, kernel-rt-debug-6.12.0-55.69.1.el10_0 +11
  • RHSA-2026:6940 Released 2026-04-08 · Red Hat rating Moderate
    kernel security update
    • Red Hat CodeReady Linux Builder EUS (v.9.6) kernel-tools-libs-devel-5.14.0-570.106.1.el9_6, libperf-5.14.0-570.106.1.el9_6
    • Red Hat Enterprise Linux AppStream EUS (v.9.6) kernel-64k-debug-devel-5.14.0-570.106.1.el9_6, kernel-64k-debug-devel-matched-5.14.0-570.106.1.el9_6, kernel-64k-devel-5.14.0-570.106.1.el9_6 +12
    • Red Hat Enterprise Linux BaseOS EUS (v.9.6) kernel-5.14.0-570.106.1.el9_6, kernel-64k-5.14.0-570.106.1.el9_6, kernel-64k-core-5.14.0-570.106.1.el9_6 +28
    • Red Hat Enterprise Linux Real Time EUS (v.9.6) kernel-rt-5.14.0-570.106.1.el9_6, kernel-rt-64k-5.14.0-570.106.1.el9_6, kernel-rt-64k-core-5.14.0-570.106.1.el9_6 +21
    • Red Hat Enterprise Linux Real Time for NFV EUS (v.9.6) kernel-rt-5.14.0-570.106.1.el9_6, kernel-rt-core-5.14.0-570.106.1.el9_6, kernel-rt-debug-5.14.0-570.106.1.el9_6 +11
  • RHSA-2026:6570 Released 2026-04-06 · Red Hat rating Moderate
    kernel security update
    • Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-611.47.1.el9_7, kernel-64k-debug-devel-matched-5.14.0-611.47.1.el9_7, kernel-64k-devel-5.14.0-611.47.1.el9_7 +12
    • Red Hat Enterprise Linux BaseOS (v. 9) kernel-5.14.0-611.47.1.el9_7, kernel-64k-5.14.0-611.47.1.el9_7, kernel-64k-core-5.14.0-611.47.1.el9_7 +28
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) kernel-tools-libs-devel-5.14.0-611.47.1.el9_7, libperf-5.14.0-611.47.1.el9_7
    • Red Hat Enterprise Linux Real Time (v. 9) kernel-rt-5.14.0-611.47.1.el9_7, kernel-rt-64k-5.14.0-611.47.1.el9_7, kernel-rt-64k-core-5.14.0-611.47.1.el9_7 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 9) kernel-rt-5.14.0-611.47.1.el9_7, kernel-rt-core-5.14.0-611.47.1.el9_7, kernel-rt-debug-5.14.0-611.47.1.el9_7 +9
  • RHSA-2026:6571 Released 2026-04-06 · Red Hat rating Moderate
    kernel security update
    • Red Hat Enterprise Linux BaseOS (v. 8) bpftool-4.18.0-553.117.1.el8_10, kernel-4.18.0-553.117.1.el8_10, kernel-abi-stablelists-4.18.0-553.117.1.el8_10 +19
    • Red Hat Enterprise Linux CRB (v. 8) kernel-tools-libs-devel-4.18.0-553.117.1.el8_10
  • RHSA-2026:6572 Released 2026-04-06 · Red Hat rating Moderate
    kernel-rt security update
    • Red Hat Enterprise Linux NFV (v. 8) kernel-rt-4.18.0-553.117.1.rt7.458.el8_10, kernel-rt-core-4.18.0-553.117.1.rt7.458.el8_10, kernel-rt-debug-4.18.0-553.117.1.rt7.458.el8_10 +9
    • Red Hat Enterprise Linux RT (v. 8) kernel-rt-4.18.0-553.117.1.rt7.458.el8_10, kernel-rt-core-4.18.0-553.117.1.rt7.458.el8_10, kernel-rt-debug-4.18.0-553.117.1.rt7.458.el8_10 +7
  • RHSA-2026:6053 Released 2026-03-30 · Red Hat rating Moderate
    kernel security update
    • Red Hat Enterprise Linux AppStream (v. 10) kernel-64k-debug-devel-6.12.0-124.47.1.el10_1, kernel-64k-debug-devel-matched-6.12.0-124.47.1.el10_1, kernel-64k-devel-6.12.0-124.47.1.el10_1 +12
    • Red Hat Enterprise Linux BaseOS (v. 10) kernel-6.12.0-124.47.1.el10_1, kernel-64k-6.12.0-124.47.1.el10_1, kernel-64k-core-6.12.0-124.47.1.el10_1 +29
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) kernel-tools-libs-devel-6.12.0-124.47.1.el10_1, libperf-6.12.0-124.47.1.el10_1
    • Red Hat Enterprise Linux Real Time (v. 10) kernel-rt-6.12.0-124.47.1.el10_1, kernel-rt-64k-6.12.0-124.47.1.el10_1, kernel-rt-64k-core-6.12.0-124.47.1.el10_1 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 10) kernel-rt-6.12.0-124.47.1.el10_1, kernel-rt-core-6.12.0-124.47.1.el10_1, kernel-rt-debug-6.12.0-124.47.1.el10_1 +9

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 9AffectedNo fix yet
Red Hat CodeReady Linux Builder EUS (v.9.4)Fixed RHSA-2026:10108
Red Hat CodeReady Linux Builder EUS (v.9.6)Fixed RHSA-2026:6940
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2026:6053
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2026:6570
Red Hat Enterprise Linux AppStream E4S (v.9.0)Fixed RHSA-2026:9836
Red Hat Enterprise Linux AppStream E4S (v.9.2)Fixed RHSA-2026:9644
Red Hat Enterprise Linux AppStream EUS (v. 10.0)Fixed RHSA-2026:9095
Red Hat Enterprise Linux AppStream EUS (v.9.4)Fixed RHSA-2026:10108
Red Hat Enterprise Linux AppStream EUS (v.9.6)Fixed RHSA-2026:6940
Red Hat Enterprise Linux BaseOS (v. 10)Fixed RHSA-2026:6053
Red Hat Enterprise Linux BaseOS (v. 8)Fixed RHSA-2026:6571
Red Hat Enterprise Linux BaseOS (v. 9)Fixed RHSA-2026:6570
Red Hat Enterprise Linux BaseOS AUS (v. 8.2)Fixed RHSA-2026:9513
Red Hat Enterprise Linux BaseOS AUS (v.8.4)Fixed RHSA-2026:9643
Red Hat Enterprise Linux BaseOS AUS (v.8.6)Fixed RHSA-2026:9514
Red Hat Enterprise Linux BaseOS E4S (v.8.6)Fixed RHSA-2026:9514
Red Hat Enterprise Linux BaseOS E4S (v.8.8)Fixed RHSA-2026:9515
Red Hat Enterprise Linux BaseOS E4S (v.9.0)Fixed RHSA-2026:9836
Red Hat Enterprise Linux BaseOS E4S (v.9.2)Fixed RHSA-2026:9644
Red Hat Enterprise Linux BaseOS EUS (v. 10.0)Fixed RHSA-2026:9095
Red Hat Enterprise Linux BaseOS EUS (v.9.4)Fixed RHSA-2026:10108
Red Hat Enterprise Linux BaseOS EUS (v.9.6)Fixed RHSA-2026:6940
Red Hat Enterprise Linux BaseOS EUS EXTENSION (v.8.4)Fixed RHSA-2026:9643
Red Hat Enterprise Linux BaseOS TUS (v.8.6)Fixed RHSA-2026:9514
Red Hat Enterprise Linux BaseOS TUS (v.8.8)Fixed RHSA-2026:9515
Red Hat Enterprise Linux CRB (v. 8)Fixed RHSA-2026:6571
Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)Fixed RHSA-2026:6053
Red Hat Enterprise Linux CodeReady Linux Builder (v. 9)Fixed RHSA-2026:6570
Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0)Fixed RHSA-2026:9095
Red Hat Enterprise Linux NFV (v. 8)Fixed RHSA-2026:6572
Red Hat Enterprise Linux NFV E4S (v.9.0)Fixed RHSA-2026:9835
Red Hat Enterprise Linux RT (v. 8)Fixed RHSA-2026:6572
Red Hat Enterprise Linux Real Time (v. 10)Fixed RHSA-2026:6053
Red Hat Enterprise Linux Real Time (v. 9)Fixed RHSA-2026:6570
Red Hat Enterprise Linux Real Time E4S (v.9.0)Fixed RHSA-2026:9835
Red Hat Enterprise Linux Real Time E4S (v.9.2)Fixed RHSA-2026:9512
Red Hat Enterprise Linux Real Time EUS (v. 10.0)Fixed RHSA-2026:9095
Red Hat Enterprise Linux Real Time EUS (v.9.4)Fixed RHSA-2026:10108
Red Hat Enterprise Linux Real Time EUS (v.9.6)Fixed RHSA-2026:6940
Red Hat Enterprise Linux Real Time for NFV (v. 10)Fixed RHSA-2026:6053
Red Hat Enterprise Linux Real Time for NFV (v. 9)Fixed RHSA-2026:6570
Red Hat Enterprise Linux Real Time for NFV E4S (v.9.2)Fixed RHSA-2026:9512
Red Hat Enterprise Linux Real Time for NFV EUS (v. 10.0)Fixed RHSA-2026:9095
Red Hat Enterprise Linux Real Time for NFV EUS (v.9.4)Fixed RHSA-2026:10108
Red Hat Enterprise Linux Real Time for NFV EUS (v.9.6)Fixed RHSA-2026:6940
Red Hat Enterprise Linux Server (v. 7 ELS)Fixed RHSA-2026:9870
Red Hat Enterprise Linux Server Optional (v. 7 ELS)Fixed RHSA-2026:9870
Red Hat Enterprise Linux for Real Time (v. 7 ELS)Fixed RHSA-2026:10756
Not affected: 1 product
  • Red Hat Enterprise Linux 6

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-23231
  2. 2026-10-03 Alias added: GHSA-gxm6-px42-mpjc
  3. 2026-10-19 Weakness changed · CISA ADP

References

Patch 6

  • TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
  • TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
  • TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
  • TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
  • TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
See all 15278 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences