Incorrect calculation in Linux kernel - CVE-2026-72021

Vulnerability identifier: #VU143565

CSH Severity: Medium

CVSS v4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-72021

CWE-ID: CWE-682

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to cause incorrect connection state tracking.

The vulnerability exists due to improper calculation of buffer offsets in SCTP state lookup in net/netfilter/ipvs/ip_vs_proto_sctp.c when processing IPv6 SCTP packets with extension headers. A remote attacker can send a specially crafted IPv6 SCTP packet with extension headers to cause incorrect connection state tracking.

This can cause an SCTP connection to be moved to the established state before the SCTP handshake has completed, resulting in incorrect timeout handling and destination counter updates.

Linux kernel
openEuler
python3-perf-debuginfo
python3-perf
perf-debuginfo
perf
kernel-tools-devel
kernel-tools-debuginfo
kernel-tools
kernel-source
kernel-headers
kernel-devel
kernel-debugsource
kernel-debuginfo
bpftool-debuginfo
bpftool
kernel
kernel-extra-modules

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
python3-perf-debuginfo - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
python3-perf - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
perf-debuginfo - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
perf - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
kernel-tools-devel - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
kernel-tools-debuginfo - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
kernel-tools - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
kernel-source - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
kernel-headers - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
kernel-devel - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
kernel-debugsource - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
kernel-debuginfo - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
bpftool-debuginfo - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
bpftool - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
kernel - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
kernel-extra-modules - update to 6.6.0-145.3.29.160

• https://git.kernel.org/stable/c/247d055504dcc852e539b9f7f30d19f9741474bf
• https://git.kernel.org/stable/c/290e9e8389b556efc603522e28bd1543846aa336
• https://git.kernel.org/stable/c/2f75c0faa3361b28e36cc0512b3299e163e25789
• https://git.kernel.org/stable/c/9cb5ac594ca76d3a71803b23b74c835b0721e628
• https://git.kernel.org/stable/c/9f94573ab962a9e81954b755da016fa3cd2f5039
• https://git.kernel.org/stable/c/a4a2d2e483d79cc2ad3a170674cf159644acf22b
• https://git.kernel.org/stable/c/d2b8b1557ec07ea1bb5dddbceaf4dfe63d388e27
• https://git.kernel.org/stable/c/e5d0bb8871668f20de8f3c94b5ae3f372346bc6e

• Incorrect calculation in Linux kernel netfilter ipvs
• openEuler 24.03 LTS SP3 update for kernel
• openEuler 24.03 LTS SP1 update for kernel