{
  "affected": [
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:14",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "details": "In the Linux kernel, the following vulnerability has been resolved:  ipv6: null-check fib6_node before accessing in __ip6_del_rt_siblings()  syzbot reported a null-ptr-deref in __ip6_del_rt_siblings() [0].  The stack trace hinted towards a null dereference of rt-\u003efib6_node when fn-\u003eleaf is accessed in __ip6_del_rt_siblings(). With RTNL_FLAG_DOIT_UNLOCKED set, inet6_rtm_delroute() operations run concurrently without acquiring the RTNL lock. In ip6_route_del(), the route lookup happens under rcu_read_lock() without acquiring table-\u003etb6_lock.  Between ip6_route_del() looking up the route and __ip6_del_rt_siblings() acquiring table-\u003etb6_lock, another thread can modify the routing table. For example, when an ECMP route is replaced via RTM_NEWROUTE with NLM_F_REPLACE, fib6_add_rt2node() unlinks all old siblings and sets iter-\u003efib6_node = NULL. A reproducer was found that triggers this [1].  Add a check to ensure rt-\u003efib6_node is non-null before accessing it.  [0] KASAN: null-ptr-deref in range [0x0000000000000020-0x0000000000000027] RIP: 0010:__ip6_del_rt_siblings+0x31e/0x7c0 net/ipv6/route.c:4056 Call Trace:  \u003cTASK\u003e  ip6_route_del+0x1054/0x1110 net/ipv6/route.c:4232  inet6_rtm_delroute+0x5d7/0x6d0 net/ipv6/route.c:5669  rtnetlink_rcv_msg+0x802/0xc00 net/core/rtnetlink.c:7132  netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2556  netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]  netlink_unicast+0x7f5/0x990 net/netlink/af_netlink.c:1345  netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1900  sock_sendmsg_nosec+0x13a/0x180 net/socket.c:800  __sock_sendmsg net/socket.c:815 [inline]  ____sys_sendmsg+0x565/0x870 net/socket.c:2713  ___sys_sendmsg+0x2a5/0x360 net/socket.c:2767  __sys_sendmsg net/socket.c:2799 [inline]  __do_sys_sendmsg net/socket.c:2804 [inline]  __se_sys_sendmsg net/socket.c:2802 [inline]  __x64_sys_sendmsg+0x1b7/0x290 net/socket.c:2802  do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]  do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84  entry_SYSCALL_64_after_hwframe+0x77/0x7f  \u003c/TASK\u003e  [1] https://gist.github.com/NamanGulati/0766a1159b6ca61928faaf87425ff899",
  "id": "DEBIAN-CVE-2026-97974",
  "modified": "2026-09-26T04:47:34.003820015Z",
  "published": "2026-09-25T11:17:25.310Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://security-tracker.debian.org/tracker/CVE-2026-97974"
    }
  ],
  "upstream": [
    "CVE-2026-97974"
  ]
}