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.
Affected products
linux: linux kernel
References9
- git.kernel.org/stable/c/2094a7cf91b71367b649f991aacc7b579f793d0b Patch
- git.kernel.org/stable/c/33670f780e0120c3dacda188c512bbffe0b6044c Patch
- git.kernel.org/stable/c/732fdeb2987c94b439d51f5cb9addddc2fc48c42 Patch
- git.kernel.org/stable/c/a98b78116a27e2a57b696b569b2cb431c95cf9b6 Patch
- git.kernel.org/stable/c/c4336a07eb6b2526dc2b62928b5104b41a7f81f5 Patch
- git.kernel.org/stable/c/ed71cf465c75f5688b07a35d373cd1d6b589c8ea Patch
- cert-portal.siemens.com/productcert/html/ssa-019113.html
- cert-portal.siemens.com/productcert/html/ssa-082556.html
- cert-portal.siemens.com/productcert/html/ssa-457936.html
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 39 · as of 13 November 2026
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