{
  "affected": [
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:12",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "6.1.170-1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:13",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "6.12.85-1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:14",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "6.18.14-1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "details": "In the Linux kernel, the following vulnerability has been resolved:  xfrm: fix ip_rt_bug race in icmp_route_lookup reverse path  icmp_route_lookup() performs multiple route lookups to find a suitable route for sending ICMP error messages, with special handling for XFRM (IPsec) policies.  The lookup sequence is: 1. First, lookup output route for ICMP reply (dst = original src) 2. Pass through xfrm_lookup() for policy check 3. If blocked (-EPERM) or dst is not local, enter \"reverse path\" 4. In reverse path, call xfrm_decode_session_reverse() to get fl4_dec    which reverses the original packet's flow (saddr\u003c-\u003edaddr swapped) 5. If fl4_dec.saddr is local (we are the original destination), use    __ip_route_output_key() for output route lookup 6. If fl4_dec.saddr is NOT local (we are a forwarding node), use    ip_route_input() to simulate the reverse packet's input path 7. Finally, pass rt2 through xfrm_lookup() with XFRM_LOOKUP_ICMP flag  The bug occurs in step 6: ip_route_input() is called with fl4_dec.daddr (original packet's source) as destination. If this address becomes local between the initial check and ip_route_input() call (e.g., due to concurrent \"ip addr add\"), ip_route_input() returns a LOCAL route with dst.output set to ip_rt_bug.  This route is then used for ICMP output, causing dst_output() to call ip_rt_bug(), triggering a WARN_ON:   ------------[ cut here ]------------  WARNING: net/ipv4/route.c:1275 at ip_rt_bug+0x21/0x30, CPU#1  Call Trace:   \u003cTASK\u003e   ip_push_pending_frames+0x202/0x240   icmp_push_reply+0x30d/0x430   __icmp_send+0x1149/0x24f0   ip_options_compile+0xa2/0xd0   ip_rcv_finish_core+0x829/0x1950   ip_rcv+0x2d7/0x420   __netif_receive_skb_one_core+0x185/0x1f0   netif_receive_skb+0x90/0x450   tun_get_user+0x3413/0x3fb0   tun_chr_write_iter+0xe4/0x220   ...  Fix this by checking rt2-\u003ert_type after ip_route_input(). If it's RTN_LOCAL, the route cannot be used for output, so treat it as an error.  The reproducer requires kernel modification to widen the race window, making it unsuitable as a selftest. It is available at:    https://gist.github.com/mrpre/eae853b72ac6a750f5d45d64ddac1e81",
  "id": "DEBIAN-CVE-2026-45905",
  "modified": "2026-09-14T16:47:48.880793397Z",
  "published": "2026-05-27T14:17:04.993Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://security-tracker.debian.org/tracker/CVE-2026-45905"
    }
  ],
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "upstream": [
    "CVE-2026-45905"
  ]
}