{"api_version":"1","generated_at":"2026-11-04T05:40:49+00:00","cve":"CVE-2026-98303","urls":{"html":"https://cve.report/CVE-2026-98303","api":"https://cve.report/api/cve/CVE-2026-98303.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-98303","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-98303"},"summary":{"title":"ipv4: icmp: reject RTN_UNREACHABLE input routes in icmp_route_lookup","description":"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.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-10-06 09:18:21","updated_at":"2026-10-19 10:18:32"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/1af2d87964d87ba7626d96928d68c09158b5a223","name":"https://git.kernel.org/stable/c/1af2d87964d87ba7626d96928d68c09158b5a223","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/2998147b59c9df0a51477c7a6b3d1f0ba3127dd4","name":"https://git.kernel.org/stable/c/2998147b59c9df0a51477c7a6b3d1f0ba3127dd4","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/fda3000147dc96c75ba162f680bec0a9fecf3037","name":"https://git.kernel.org/stable/c/fda3000147dc96c75ba162f680bec0a9fecf3037","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/83aa83f81a8fec30ff5372dee60b2f0561bcb2ca","name":"https://git.kernel.org/stable/c/83aa83f81a8fec30ff5372dee60b2f0561bcb2ca","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/06083cea4a3b95f5ebc85312f97d7086e6c9e782","name":"https://git.kernel.org/stable/c/06083cea4a3b95f5ebc85312f97d7086e6c9e782","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/cac69c50716c712ef0114837c9427da66066124c","name":"https://git.kernel.org/stable/c/cac69c50716c712ef0114837c9427da66066124c","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-98303","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98303","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 8b7817f3a959ed99d7443afc12f78a7e1fcc2063 06083cea4a3b95f5ebc85312f97d7086e6c9e782 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 8b7817f3a959ed99d7443afc12f78a7e1fcc2063 83aa83f81a8fec30ff5372dee60b2f0561bcb2ca git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 8b7817f3a959ed99d7443afc12f78a7e1fcc2063 cac69c50716c712ef0114837c9427da66066124c git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 8b7817f3a959ed99d7443afc12f78a7e1fcc2063 1af2d87964d87ba7626d96928d68c09158b5a223 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 8b7817f3a959ed99d7443afc12f78a7e1fcc2063 fda3000147dc96c75ba162f680bec0a9fecf3037 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 8b7817f3a959ed99d7443afc12f78a7e1fcc2063 2998147b59c9df0a51477c7a6b3d1f0ba3127dd4 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 2.6.25","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 2.6.25 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.1.189 6.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.6.158 6.6.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.112 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.54 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2.8 7.2.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.3 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"98303","cve":"CVE-2026-98303","epss":"0.001800000","percentile":"0.069220000","score_date":"2026-10-06","updated_at":"2026-10-07 00:14:55"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["net/ipv4/icmp.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"06083cea4a3b95f5ebc85312f97d7086e6c9e782","status":"affected","version":"8b7817f3a959ed99d7443afc12f78a7e1fcc2063","versionType":"git"},{"lessThan":"83aa83f81a8fec30ff5372dee60b2f0561bcb2ca","status":"affected","version":"8b7817f3a959ed99d7443afc12f78a7e1fcc2063","versionType":"git"},{"lessThan":"cac69c50716c712ef0114837c9427da66066124c","status":"affected","version":"8b7817f3a959ed99d7443afc12f78a7e1fcc2063","versionType":"git"},{"lessThan":"1af2d87964d87ba7626d96928d68c09158b5a223","status":"affected","version":"8b7817f3a959ed99d7443afc12f78a7e1fcc2063","versionType":"git"},{"lessThan":"fda3000147dc96c75ba162f680bec0a9fecf3037","status":"affected","version":"8b7817f3a959ed99d7443afc12f78a7e1fcc2063","versionType":"git"},{"lessThan":"2998147b59c9df0a51477c7a6b3d1f0ba3127dd4","status":"affected","version":"8b7817f3a959ed99d7443afc12f78a7e1fcc2063","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["net/ipv4/icmp.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"2.6.25"},{"lessThan":"2.6.25","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.1.*","status":"unaffected","version":"6.1.189","versionType":"semver"},{"lessThanOrEqual":"6.6.*","status":"unaffected","version":"6.6.158","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.112","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.54","versionType":"semver"},{"lessThanOrEqual":"7.2.*","status":"unaffected","version":"7.2.8","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.3","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.1.189","versionStartIncluding":"2.6.25","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.6.158","versionStartIncluding":"2.6.25","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.112","versionStartIncluding":"2.6.25","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.54","versionStartIncluding":"2.6.25","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2.8","versionStartIncluding":"2.6.25","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.3","versionStartIncluding":"2.6.25","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"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."}],"providerMetadata":{"dateUpdated":"2026-10-19T09:17:14.136Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/06083cea4a3b95f5ebc85312f97d7086e6c9e782"},{"url":"https://git.kernel.org/stable/c/83aa83f81a8fec30ff5372dee60b2f0561bcb2ca"},{"url":"https://git.kernel.org/stable/c/cac69c50716c712ef0114837c9427da66066124c"},{"url":"https://git.kernel.org/stable/c/1af2d87964d87ba7626d96928d68c09158b5a223"},{"url":"https://git.kernel.org/stable/c/fda3000147dc96c75ba162f680bec0a9fecf3037"},{"url":"https://git.kernel.org/stable/c/2998147b59c9df0a51477c7a6b3d1f0ba3127dd4"}],"title":"ipv4: icmp: reject RTN_UNREACHABLE input routes in icmp_route_lookup","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-98303","datePublished":"2026-10-06T08:46:00.524Z","dateReserved":"2026-09-25T10:25:14.338Z","dateUpdated":"2026-10-19T09:17:14.136Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-10-06 09:18:21","lastModifiedDate":"2026-10-19 10:18:32","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"98303","Ordinal":"1","Title":"ipv4: icmp: reject RTN_UNREACHABLE input routes in icmp_route_lo","CVE":"CVE-2026-98303","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"98303","Ordinal":"1","NoteData":"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.","Type":"Description","Title":"ipv4: icmp: reject RTN_UNREACHABLE input routes in icmp_route_lo"}]}}}