CVE-2026-43198tcp: fix potential race in tcp_v6_syn_recv_sock()
Updated under an hour ago ()
Does this affect you?
It affects Linux and 10 other products. Add what you run to find out whether that includes you.
No exploitation reported and no EPSS estimate yet.
Do this next
Free account, 1 product
In the Linux kernel, the following vulnerability has been resolved: tcp: fix potential race in tcp_v6_syn_recv_sock() Code in tcp_v6_syn_recv_sock() after the call to tcp_v4_syn_recv_sock() is done too late. After tcp_v4_syn_recv_sock(), the child socket is already visible from TCP ehash table and other cpus might use it. Since newinet->pinet6 is still pointing to the listener ipv6_pinfo bad things can happen as syzbot found. Move the problematic code in tcp_v6_mapped_child_init() and call this new helper from tcp_v4_syn_recv_sock() before the ehash insertion. This allows the removal of one tcp_sync_mss(), since tcp_v4_syn_recv_sock() will call it with the correct context.
- CVSS
- 9.8 CRITICAL (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Weakness (CWE)
- CWE-821
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- Not loaded for this CVE
- Assigned by
- Linux
- NVD analysis
- Modified
- Record last updated
- Oct 16, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
Linux Linux linux:linux (from the name) | from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 before aef4a9ae95d1bc4f7897065011e6261026719aeb; from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 before dad1fe7db6c6519138430ac8f5e589c18f83bfc9; from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 before a7e761ba55efaa9c49e0afdd304bb78167af3429; from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 before cd644e6dc72eec8d9d988717ea1c54f8668ded69; from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 before 9ed654e340f4c73bc6f0af2fbc90ac293e645ce0; from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 before fe89b2f05b854847784f91127319172945c1fadd; from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 before 7178e2a8027423b2af17ab95df73a749a5b72e5b; from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 before 858d2a4f67ff69e645a43487ef7ea7f28f06deae | CNA record |
Red Hat Red Hat Enterprise Linux 10 redhat:enterprise_linux | from 0:6.12.0-211.28.1.el10_2 not affected | CISA ADP |
Red Hat Red Hat Enterprise Linux 10.0 Extended Update Support redhat:enterprise_linux_eus | from 0:6.12.0-55.84.1.el10_0 not affected | CISA ADP |
Red Hat Red Hat Enterprise Linux 7 Extended Lifecycle Support redhat:rhel_extras_rt_els | from 0:3.10.0-1160.155.1.rt56.1307.el7 not affected | CISA ADP |
from 0:3.10.0-1160.155.1.el7 not affected | CISA ADP | |
from 0:4.18.0-305.197.1.el8_4 not affected | CISA ADP | |
Red Hat Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On redhat:rhel_eus_long_life | from 0:4.18.0-305.197.1.el8_4 not affected | CISA ADP |
from 0:4.18.0-477.150.1.el8_8 not affected | CISA ADP | |
from 0:4.18.0-477.150.1.el8_8 not affected | CISA ADP | |
Red Hat Red Hat Enterprise Linux 9.6 Extended Update Support redhat:rhel_eus | from 0:5.14.0-570.125.1.el9_6 not affected | CISA ADP |
linux linux_kernel linux:linux_kernel | from 2.6.12.1 before 6.18.16; from 6.19 before 6.19.6; 2.6.12; 2.6.12; 2.6.12; 2.6.12; 2.6.12; 7.0 | NVD |
References
- https://git.kernel.org/stable/c/aef4a9ae95d1bc4f7897065011e6261026719aeb
- https://git.kernel.org/stable/c/dad1fe7db6c6519138430ac8f5e589c18f83bfc9
- https://git.kernel.org/stable/c/a7e761ba55efaa9c49e0afdd304bb78167af3429
- https://git.kernel.org/stable/c/cd644e6dc72eec8d9d988717ea1c54f8668ded69
- https://git.kernel.org/stable/c/9ed654e340f4c73bc6f0af2fbc90ac293e645ce0
- https://git.kernel.org/stable/c/fe89b2f05b854847784f91127319172945c1faddpatch
- https://git.kernel.org/stable/c/7178e2a8027423b2af17ab95df73a749a5b72e5bpatch
- https://git.kernel.org/stable/c/858d2a4f67ff69e645a43487ef7ea7f28f06deaepatch
- https://access.redhat.com/errata/RHSA-2026:30129
- https://access.redhat.com/errata/RHSA-2026:33215
- https://access.redhat.com/errata/RHSA-2026:33285
- https://access.redhat.com/errata/RHSA-2026:34094
- https://access.redhat.com/errata/RHSA-2026:34443
- https://access.redhat.com/errata/RHSA-2026:35863
- https://access.redhat.com/errata/RHSA-2026:35894
- https://access.redhat.com/errata/RHSA-2026:35896
- https://access.redhat.com/errata/RHSA-2026:35904
- https://access.redhat.com/errata/RHSA-2026:36073
- https://access.redhat.com/errata/RHSA-2026:36216
- https://access.redhat.com/errata/RHSA-2026:36348
- https://access.redhat.com/errata/RHSA-2026:36349
- https://access.redhat.com/errata/RHSA-2026:41236
- https://access.redhat.com/security/cve/CVE-2026-43198
- https://bugzilla.redhat.com/show_bug.cgi?id=2467228
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-43198.json
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.