CVE-2026-43198
Description
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.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
OS impact
Linux kernel Affected 3 releases
| Version | Status | Fixed in |
|---|---|---|
| 7.0 | Affected | — |
| 2.6.12 | Affected | — |
| — | Affected | 6.18.16 |
SUSE Affected 1 release
| Version | Status | Fixed in |
|---|---|---|
| — | Affected | — |
Windows Affected 1 release
| Version | Status | Fixed in |
|---|---|---|
| — | Affected | — |
Debian Mixed 5 releases
| Version | Status | Fixed in |
|---|---|---|
| trixie | Affected | — |
| sid | Fixed | 6.19.6-1 |
| forky | Fixed | 6.19.6-1 |
| bullseye | Affected | — |
| bookworm | Affected | — |
References
- https://git.kernel.org/stable/c/7178e2a8027423b2af17ab95df73a749a5b72e5b
- https://git.kernel.org/stable/c/858d2a4f67ff69e645a43487ef7ea7f28f06deae
- https://git.kernel.org/stable/c/fe89b2f05b854847784f91127319172945c1fadd
- https://www.suse.com/security/cve/CVE-2026-43198.html
- https://security-tracker.debian.org/tracker/CVE-2026-43198
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-43198
CWEs
CWE-362
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.