Instituto Nacional de ciberseguridad. Sección Incibe
Instituto Nacional de Ciberseguridad. Sección INCIBE-CERT

Go to Calendar     Go to Press Room     Go to Newsletters subscription

Search

CVE-2026-43198

Severity CVSS v4.0:
Pending analysis
Type:
CWE-362 Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
Publication date:
06/05/2026
Last modified:
11/05/2026

Description

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> tcp: fix potential race in tcp_v6_syn_recv_sock()<br /> <br /> Code in tcp_v6_syn_recv_sock() after the call to tcp_v4_syn_recv_sock()<br /> is done too late.<br /> <br /> After tcp_v4_syn_recv_sock(), the child socket is already visible<br /> from TCP ehash table and other cpus might use it.<br /> <br /> Since newinet-&gt;pinet6 is still pointing to the listener ipv6_pinfo<br /> bad things can happen as syzbot found.<br /> <br /> Move the problematic code in tcp_v6_mapped_child_init()<br /> and call this new helper from tcp_v4_syn_recv_sock() before<br /> the ehash insertion.<br /> <br /> This allows the removal of one tcp_sync_mss(), since<br /> tcp_v4_syn_recv_sock() will call it with the correct<br /> context.

Impact

Vector 3.x
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H CVSS v3.1 Severity and Metrics:

Base Score: 9.80 CRITICAL
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): None
Scope (S): Unchanged
Confidentiality (C): High
Integrity (I): High
Availability (A): High

Base Score 3.x
9.80
Severity 3.x
CRITICAL

Vulnerable products and versions

CPE From Up to
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* 2.6.12.1 (including) 6.18.16 (excluding)
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* 6.19 (including) 6.19.6 (excluding)
cpe:2.3:o:linux:linux_kernel:2.6.12:-:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:2.6.12:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:2.6.12:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:2.6.12:rc4:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:2.6.12:rc5:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*

To consult the complete list of CPE names with products and versions, see this page


References to Advisories, Solutions, and Tools