CVE-2026-52915

In the Linux kernel, the following vulnerability has been resolved: netfilter: ip6t_hbh: reject oversized option lists struct ip6t_opts stores at most IP6T_OPTS_OPTSNR option descriptors, but hbh_mt6_check() does not reject larger optsnr values supplied from userspace. Validate optsnr in the rule setup path so only match data that fits the fixed-size opts array can be installed. This follows the existing xtables pattern of rejecting invalid user-provided counts in checkentry() and keeps the packet matching path unchanged. `struct ip6t_opts` has a fixed `opts[IP6T_OPTS_OPTSNR]` array, where `IP6T_OPTS_OPTSNR` is 16, then off-by-one array access is possible: [ 137.924693][ T8692] UBSAN: array-index-out-of-bounds in ../net/ipv6/netfilter/ip6t_hbh.c:110:29 [ 137.926167][ T8692] index 16 is out of range for type '__u16 [16]'

• linux linux kernel (>= 2.6.12.1 < 5.10.258) • linux linux kernel (>= 5.11 < 5.15.209) • linux linux kernel (>= 5.16 < 6.1.175) • linux linux kernel (>= 6.2 < 6.6.142) • linux linux kernel (>= 6.7 < 6.12.92) • linux linux kernel (>= 6.13 < 6.18.34) • linux linux kernel (>= 6.19 < 7.0.11) • linux linux kernel 2.6.12 • linux linux kernel 7.1