The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - xfrm: fix sk_dst_cache double-free in xfrm_user_policy() xfrm_user_policy() clears the socket dst cache     with __sk_dst_reset(), i.e. the non-atomic __sk_dst_set(sk, NULL): it reads sk_dst_cache with     rcu_dereference_protected(), stores NULL and dst_release()s the old dst. That is only safe if no other     thread modifies sk_dst_cache concurrently. For a connected UDP socket that does not hold: the transmit     fast path (udp_sendmsg -> sk_dst_check -> sk_dst_reset) resets the cache locklessly with an atomic xchg().
    A per-socket policy change racing a send can make both sides observe the same old dst and each     dst_release() it, dropping the socket's single reference twice and freeing the xfrm_dst bundle while it is     still referenced: BUG: KASAN: slab-use-after-free in dst_release Write of size 4 at addr ffff88801897b6c0     by task exploit/155 Call Trace: ... dst_release (... ./include/linux/rcuref.h:109) xfrm_user_policy     (./include/net/sock.h:2239 ./include/net/sock.h:2256 net/xfrm/xfrm_state.c:3053) do_ip_setsockopt     (net/ipv4/ip_sockglue.c:1347) ip_setsockopt (net/ipv4/ip_sockglue.c:1417) do_sock_setsockopt     (net/socket.c:2368) __sys_setsockopt (net/socket.c:2393) __x64_sys_setsockopt (net/socket.c:2396)     do_syscall_64 (arch/x86/entry/syscall_64.c:94) entry_SYSCALL_64_after_hwframe     (arch/x86/entry/entry_64.S:121) Reachable by an unprivileged user via a user+network namespace. Use the     atomic sk_dst_reset() so the cache is cleared and released with a single xchg(): whichever side wins     releases the dst once, the other sees NULL and does nothing. Behaviour is otherwise unchanged.
    (CVE-2026-64581)

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Linux Distros Unpatched Vulnerability : CVE-2026-64581

high Nessus Plugin ID 332750

Version 1.2