CVE-2026-43057

High

Description

In the Linux kernel, the following vulnerability has been resolved: net: correctly handle tunneled traffic on IPV6_CSUM GSO fallback NETIF_F_IPV6_CSUM only advertises support for checksum offload of packets without IPv6 extension headers. Packets with extension headers must fall back onto software checksumming. Since TSO depends on checksum offload, those must revert to GSO. The below commit introduces that fallback. It always checks network header length. For tunneled packets, the inner header length must be checked instead. Extend the check accordingly. A special case is tunneled packets without inner IP protocol. Such as RFC 6951 SCTP in UDP. Those are not standard IPv6 followed by transport header either, so also must revert to the software GSO path.

SeverityHigh
CVSS7.5
Exploit probability—
ProductLinux Kernel
PublishedMay 1, 2026
First seenMay 1, 2026

How to fix

Update
  • linux linux_kernel6.1.168, 6.6.134, 6.12.81, 6.17, 6.18.22, 6.19.12 or later

Affected products

ProductAffected versionsFixed in
linux linux_kernel6.1.149 ≤ v < 6.1.168, 6.6.103 ≤ v < 6.6.134, 6.12.44 ≤ v < 6.12.81, 6.16.4 ≤ v < 6.17, 6.17.1 < v < 6.18.22, 6.19 ≤ v < 6.19.12, 6.17, 7.06.1.168, 6.6.134, 6.12.81, 6.17, 6.18.22, 6.19.12

Check your version

Choose the product and enter the version you run to see whether it falls in the affected range.

In the Intelligence 360 plan

Attack Surface Management

See the assets tied to your domains, the technologies they run and known vulnerabilities in one list.