{"id":"AZL-106917","summary":"CVE-2026-98379 affecting package kernel 6.6.157.1-1","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: ip6t_rpfilter: reject routes without inet6_dev\n\nip6_route_lookup() can return an error-free route whose rt6i_idev is\nNULL. Lowering an external nexthop device's MTU below IPV6_MIN_MTU tears\ndown its inet6_dev while fib6_ifdown() leaves routes using nexthop objects\nin the FIB. An unprivileged user can construct this state with rtnetlink\nin a private user and network namespace, then trigger a NULL dereference\nthrough an IPv6 rpfilter lookup:\n\n  Oops: general protection fault, probably for non-canonical address\n  0xdffffc0000000000\n  KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]\n  RIP: rpfilter_mt (net/ipv6/netfilter/ip6t_rpfilter.c:75)\n  Call Trace:\n  ip6t_do_table (net/ipv6/netfilter/ip6_tables.c:316)\n  nf_hook_slow (net/netfilter/core.c:619)\n  ipv6_rcv (net/ipv6/ip6_input.c:351)\n  __netif_receive_skb_one_core (net/core/dev.c:6216)\n  process_backlog (net/core/dev.c:6680)\n  __napi_poll (net/core/dev.c:7739)\n  net_rx_action (net/core/dev.c:7959)\n  handle_softirqs (kernel/softirq.c:622)\n  do_softirq.part.0 (kernel/softirq.c:523)\n  __local_bh_enable_ip (kernel/softirq.c:450)\n  __dev_queue_xmit (net/core/dev.c:4913)\n  packet_sendmsg (net/packet/af_packet.c:3139)\n  __sys_sendto (net/socket.c:2252)\n  __x64_sys_sendto (net/socket.c:2259)\n  do_syscall_64 (arch/x86/entry/syscall_64.c:94)\n  entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121)\n  Kernel panic - not syncing: Fatal exception in interrupt\n\nReject routes without an inet6_dev immediately after lookup. Such routes\nare not eligible for reverse-path filtering, and the check protects all\nlater rt6i_idev dereferences.","modified":"2026-10-10T14:17:32.475755119Z","published":"2026-10-09T08:16:56Z","upstream":["CVE-2026-98379"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98379"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"6.6.157.1-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-106917.json"}}],"schema_version":"1.9.0"}