CVE-2026-74561

*** Pendiente de traducción *** In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> nexthop: avoid unlocked f6i_list walk in nh_rt_cache_flush<br /> <br /> nh_rt_cache_flush() walks nh-&gt;f6i_list during an RTNL-serialized nexthop<br /> replace without holding nh-&gt;lock, racing the unlocked IPv6 route<br /> add/delete that mutate the list under nh-&gt;lock and free fib6_info<br /> entries (nh_rt_cache_flush() is inlined into rtm_new_nexthop()):<br /> <br /> BUG: KASAN: slab-use-after-free in nh_rt_cache_flush (net/ipv4/nexthop.c:2243)<br /> Read of size 8 at addr ffff888012953e18 by task exploit/146<br /> nh_rt_cache_flush (net/ipv4/nexthop.c:2243)<br /> replace_nexthop (net/ipv4/nexthop.c:2610)<br /> rtm_new_nexthop (net/ipv4/nexthop.c:3323)<br /> rtnetlink_rcv_msg (net/core/rtnetlink.c:7076)<br /> <br /> Unlike the other f6i_list walks, this one bumps each route&amp;#39;s sernum via<br /> fib6_update_sernum_upto_root(), which needs tb6_lock; taking nh-&gt;lock<br /> around it would invert the established tb6_lock -&gt; nh-&gt;lock order and<br /> deadlock. As the only purpose is to invalidate cached dsts, bump the<br /> IPv6 sernum for the whole netns with rt_genid_bump_ipv6() instead,<br /> mirroring the rt_cache_flush() already done for IPv4 just above.