Description
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.
References8
- git.kernel.org/stable/c/2fd89a50a9783eed8ed23866b11c8b3d8779a7a8
- git.kernel.org/stable/c/3578b6d92a5b1e603ae6e8c8f5538a709f03aba4
- git.kernel.org/stable/c/3d441be2b1c5e98167302fa1c7b61960a067b112
- git.kernel.org/stable/c/43ccc20b5a733226417832cf16ef45322e594990
- git.kernel.org/stable/c/d5e39e5eb6b30bc4a3bb7aba54c293cf36a806c7
- git.kernel.org/stable/c/f16d856b6af5fd0e7cb0b0212f70825b599ef72e
- git.kernel.org/stable/c/f775fcf384b06f35b612f78fa5601fee99eb6513
- git.kernel.org/stable/c/fc416870100cf16d5b9495199355a679c3a02d48
Metrics
- CVSS 3.1
-
9.1
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N - EPSS — exploit probability
- 1% percentile: 50 · as of 11 November 2026
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