CVE-2026-43198
Race Condition in Linux Kernel TCP Stack
Publication date: 2026-05-06
Last updated on: 2026-05-06
Assigner: kernel.org
Description
Description
CVSS Scores
EPSS Scores
| Probability: | |
| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| linux | linux_kernel | * |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-UNKNOWN |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
This vulnerability exists in the Linux kernel's TCP implementation, specifically in the function tcp_v6_syn_recv_sock(). The issue arises because some code is executed too late after the call to tcp_v4_syn_recv_sock(), which causes the child socket to become visible prematurely in the TCP ehash table. This premature visibility allows other CPUs to access the child socket while it is still in an inconsistent state, as the newinet->pinet6 pointer still references the listener's ipv6_pinfo. This race condition can lead to unexpected or erroneous behavior.
The fix involved moving the problematic code into a new helper function tcp_v6_mapped_child_init() and calling this helper from tcp_v4_syn_recv_sock() before the child socket is inserted into the ehash table. This ensures the child socket is fully initialized before becoming visible to other CPUs.
How can this vulnerability impact me? :
This vulnerability can lead to race conditions in the TCP stack of the Linux kernel, potentially causing instability or unexpected behavior in network connections. Since the child socket may be accessed before it is fully initialized, this could result in data corruption, denial of service, or other unpredictable network issues.