CVE-2026-43057 (GCVE-0-2026-43057)
Vulnerability from cvelistv5
Published
2026-05-01 14:15
Modified
2026-08-05 12:25
Severity ?
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Summary
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.
References
Impacted products
Vendor Product Version
Linux Linux Version: a0478d7e888028f85fa7785ea838ce0ca09398e2
Version: 2156d9e9f2e483c8c3906c0ea57ea312c1424235
Version: 041e2f945f82fdbd6fff577b79c33469430297aa
Version: 864e3396976ef41de6cc7bc366276bf4e084fff2
Version: 864e3396976ef41de6cc7bc366276bf4e084fff2
Version: 864e3396976ef41de6cc7bc366276bf4e084fff2
Version: 794ddbb7b63b6828c75967b9bcd43b086716e7a1
Version: 6.1.149   ≤
Version: 6.6.103   ≤
Version: 6.12.44   ≤
Version: 6.16.4   ≤
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