{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "8b7817f3a959ed99d7443afc12f78a7e1fcc2063"
            },
            {
              "fixed": "06083cea4a3b95f5ebc85312f97d7086e6c9e782"
            },
            {
              "fixed": "83aa83f81a8fec30ff5372dee60b2f0561bcb2ca"
            },
            {
              "fixed": "cac69c50716c712ef0114837c9427da66066124c"
            },
            {
              "fixed": "1af2d87964d87ba7626d96928d68c09158b5a223"
            },
            {
              "fixed": "fda3000147dc96c75ba162f680bec0a9fecf3037"
            },
            {
              "fixed": "2998147b59c9df0a51477c7a6b3d1f0ba3127dd4"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.6.25"
            },
            {
              "fixed": "6.1.189"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.158"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.112"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.54"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.2.8"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98303.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nipv4: icmp: reject RTN_UNREACHABLE input routes in icmp_route_lookup\n\nWhen the forward output route cannot be used in icmp_route_lookup(),\nit enters the \"reverse path\" and calls ip_route_input() on fl4_dec.daddr,\nthe original packet's source address.\n\nip_route_input() only returns an error for truly invalid packets. For\nunreachable addresses it will succeed and return an input route whose\ndst.output is set to ip_rt_bug(). The existing check only rejects\nRTN_LOCAL routes, so the RTN_UNREACHABLE route types can still be returned\nand later used for output, syzkaller triggering a WARN_ON_ONCE()\nin ip_rt_bug() as bellow:\n\n ------------[ cut here ]------------\n WARNING: net/ipv4/route.c:1273 at ip_rt_bug+0x14/0x20\n RIP: 0010:ip_rt_bug+0x14/0x20\n Call Trace:\n  ip_push_pending_frames+0xfa/0x100\n  __icmp_send+0x905/0xf10\n  ip_options_compile+0xc0/0xd0\n  ip_rcv_finish_core+0x321/0xae0\n  ip_rcv+0x1de/0x260\n  __netif_receive_skb_one_core+0x11a/0x130\n  netif_receive_skb+0x7b/0x260\n  tun_get_user+0x11bf/0x1c10\n ------------[ cut here ]------------\n\nReject input route that is RTN_UNREACHABLE to fix it. The net warning\nis only printed for RTN_LOCAL, as RTN_UNREACHABLE is not the result of\na race condition.",
  "id": "CVE-2026-98303",
  "modified": "2026-10-08T02:30:34.179458147Z",
  "published": "2026-10-06T08:46:00.524Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/06083cea4a3b95f5ebc85312f97d7086e6c9e782"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/1af2d87964d87ba7626d96928d68c09158b5a223"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/2998147b59c9df0a51477c7a6b3d1f0ba3127dd4"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/83aa83f81a8fec30ff5372dee60b2f0561bcb2ca"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/cac69c50716c712ef0114837c9427da66066124c"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/fda3000147dc96c75ba162f680bec0a9fecf3037"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98303.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-98303"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.9.0",
  "summary": "ipv4: icmp: reject RTN_UNREACHABLE input routes in icmp_route_lookup"
}