CVE-2026-72348

Summary

In the Linux kernel, the following vulnerability has been resolved:

netfilter: ip6tables: mark malformed IPv6 extension headers for hotdrop

The ah, hbh and rt matches check that the fixed extension header is present, then use the header length field to derive the advertised extension header length for matching.

For the ah match, add the missing advertised-length check. For hbh and rt, update the existing advertised-length checks. In all three cases, set hotdrop to true before returning false when the advertised extension header length exceeds the available skb data.

Returning false treats the packet as a rule mismatch. Set hotdrop to true and drop malformed packets so they cannot bypass rules intended to drop packets with these IPv6 extension headers.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < f16d856b6af5fd0e7cb0b0212f70825b599ef72eaffected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < fc416870100cf16d5b9495199355a679c3a02d48affected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < f775fcf384b06f35b612f78fa5601fee99eb6513affected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 2fd89a50a9783eed8ed23866b11c8b3d8779a7a8affected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 3578b6d92a5b1e603ae6e8c8f5538a709f03aba4affected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 3d441be2b1c5e98167302fa1c7b61960a067b112affected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < d5e39e5eb6b30bc4a3bb7aba54c293cf36a806c7affected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 43ccc20b5a733226417832cf16ef45322e594990affected
LinuxLinux2.6.12affected
LinuxLinux0 < 2.6.12unaffected
LinuxLinux5.10.261 <= 5.10.*unaffected
LinuxLinux5.15.212 <= 5.15.*unaffected
LinuxLinux6.1.178 <= 6.1.*unaffected
LinuxLinux6.6.145 <= 6.6.*unaffected
LinuxLinux6.12.97 <= 6.12.*unaffected
LinuxLinux6.18.40 <= 6.18.*unaffected
LinuxLinux7.1.5 <= 7.1.*unaffected
LinuxLinux7.2 <= *unaffected

Weaknesses

References