{"api_version":"1","generated_at":"2026-07-13T03:57:37+00:00","cve":"CVE-2026-53012","urls":{"html":"https://cve.report/CVE-2026-53012","api":"https://cve.report/api/cve/CVE-2026-53012.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-53012","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-53012"},"summary":{"title":"nexthop: fix IPv6 route referencing IPv4 nexthop","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnexthop: fix IPv6 route referencing IPv4 nexthop\n\nsyzbot reported a panic [1] [2].\n\nWhen an IPv6 nexthop is replaced with an IPv4 nexthop, the has_v4 flag\nof all groups containing this nexthop is not updated. This is because\nnh_group_v4_update is only called when replacing AF_INET to AF_INET6,\nbut the reverse direction (AF_INET6 to AF_INET) is missed.\n\nThis allows a stale has_v4=false to bypass fib6_check_nexthop, causing\nIPv6 routes to be attached to groups that effectively contain only AF_INET\nmembers. Subsequent route lookups then call nexthop_fib6_nh() which\nreturns NULL for the AF_INET member, leading to a NULL pointer\ndereference.\n\nFix by calling nh_group_v4_update whenever the family changes, not just\nAF_INET to AF_INET6.\n\nReproducer:\n\t# AF_INET6 blackhole\n\tip -6 nexthop add id 1 blackhole\n\t# group with has_v4=false\n\tip nexthop add id 100 group 1\n\t# replace with AF_INET (no -6), has_v4 stays false\n\tip nexthop replace id 1 blackhole\n\t# pass stale has_v4 check\n\tip -6 route add 2001:db8::/64 nhid 100\n\t# panic\n\tping -6 2001:db8::1\n\n[1] https://syzkaller.appspot.com/bug?id=e17283eb2f8dcf3dd9b47fe6f67a95f71faadad0\n[2] https://syzkaller.appspot.com/bug?id=8699b6ae54c9f35837d925686208402949e12ef3","state":"PUBLISHED","assigner":"Linux","published_at":"2026-06-24 17:17:12","updated_at":"2026-07-10 19:24:19"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/29c95185ba32b621fbc3800fb86e7dc3edf5c2be","name":"https://git.kernel.org/stable/c/29c95185ba32b621fbc3800fb86e7dc3edf5c2be","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/aaac3bed034239e1d75732211d9b05f30b0b4f35","name":"https://git.kernel.org/stable/c/aaac3bed034239e1d75732211d9b05f30b0b4f35","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/b3b7e850e1541f0520c4a12ec884255c30427ff6","name":"https://git.kernel.org/stable/c/b3b7e850e1541f0520c4a12ec884255c30427ff6","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/9c2d6770a5f4545a307eb66979bef7656a34d621","name":"https://git.kernel.org/stable/c/9c2d6770a5f4545a307eb66979bef7656a34d621","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/613c8f4a501421dd258b07ea614205d4e16ec845","name":"https://git.kernel.org/stable/c/613c8f4a501421dd258b07ea614205d4e16ec845","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/ceffe81a0be92afc0cd1340bc8ca46559cce9bb4","name":"https://git.kernel.org/stable/c/ceffe81a0be92afc0cd1340bc8ca46559cce9bb4","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/ad85961004fd4bd2f31209ac4b07612c6cefb9e7","name":"https://git.kernel.org/stable/c/ad85961004fd4bd2f31209ac4b07612c6cefb9e7","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/6275796f22bb382f3e9aa58ed0b4ef7bdad78cb8","name":"https://git.kernel.org/stable/c/6275796f22bb382f3e9aa58ed0b4ef7bdad78cb8","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-53012","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-53012","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 7bf4796dd09984ad1612877a82d0d139c70ae27f ceffe81a0be92afc0cd1340bc8ca46559cce9bb4 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 7bf4796dd09984ad1612877a82d0d139c70ae27f 9c2d6770a5f4545a307eb66979bef7656a34d621 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 7bf4796dd09984ad1612877a82d0d139c70ae27f 6275796f22bb382f3e9aa58ed0b4ef7bdad78cb8 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 7bf4796dd09984ad1612877a82d0d139c70ae27f aaac3bed034239e1d75732211d9b05f30b0b4f35 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 7bf4796dd09984ad1612877a82d0d139c70ae27f ad85961004fd4bd2f31209ac4b07612c6cefb9e7 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 7bf4796dd09984ad1612877a82d0d139c70ae27f 613c8f4a501421dd258b07ea614205d4e16ec845 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 7bf4796dd09984ad1612877a82d0d139c70ae27f b3b7e850e1541f0520c4a12ec884255c30427ff6 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 7bf4796dd09984ad1612877a82d0d139c70ae27f 29c95185ba32b621fbc3800fb86e7dc3edf5c2be git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5.3","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.3 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.10.258 5.10.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.15.209 5.15.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.1.175 6.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.6.141 6.6.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.91 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.33 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.0.10 7.0.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.1 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"53012","cve":"CVE-2026-53012","epss":"0.001850000","percentile":"0.082780000","score_date":"2026-07-12","updated_at":"2026-07-13 00:07:36"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["net/ipv4/nexthop.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"ceffe81a0be92afc0cd1340bc8ca46559cce9bb4","status":"affected","version":"7bf4796dd09984ad1612877a82d0d139c70ae27f","versionType":"git"},{"lessThan":"9c2d6770a5f4545a307eb66979bef7656a34d621","status":"affected","version":"7bf4796dd09984ad1612877a82d0d139c70ae27f","versionType":"git"},{"lessThan":"6275796f22bb382f3e9aa58ed0b4ef7bdad78cb8","status":"affected","version":"7bf4796dd09984ad1612877a82d0d139c70ae27f","versionType":"git"},{"lessThan":"aaac3bed034239e1d75732211d9b05f30b0b4f35","status":"affected","version":"7bf4796dd09984ad1612877a82d0d139c70ae27f","versionType":"git"},{"lessThan":"ad85961004fd4bd2f31209ac4b07612c6cefb9e7","status":"affected","version":"7bf4796dd09984ad1612877a82d0d139c70ae27f","versionType":"git"},{"lessThan":"613c8f4a501421dd258b07ea614205d4e16ec845","status":"affected","version":"7bf4796dd09984ad1612877a82d0d139c70ae27f","versionType":"git"},{"lessThan":"b3b7e850e1541f0520c4a12ec884255c30427ff6","status":"affected","version":"7bf4796dd09984ad1612877a82d0d139c70ae27f","versionType":"git"},{"lessThan":"29c95185ba32b621fbc3800fb86e7dc3edf5c2be","status":"affected","version":"7bf4796dd09984ad1612877a82d0d139c70ae27f","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["net/ipv4/nexthop.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"5.3"},{"lessThan":"5.3","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"5.10.*","status":"unaffected","version":"5.10.258","versionType":"semver"},{"lessThanOrEqual":"5.15.*","status":"unaffected","version":"5.15.209","versionType":"semver"},{"lessThanOrEqual":"6.1.*","status":"unaffected","version":"6.1.175","versionType":"semver"},{"lessThanOrEqual":"6.6.*","status":"unaffected","version":"6.6.141","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.91","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.33","versionType":"semver"},{"lessThanOrEqual":"7.0.*","status":"unaffected","version":"7.0.10","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.1","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"5.10.258","versionStartIncluding":"5.3","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"5.15.209","versionStartIncluding":"5.3","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.1.175","versionStartIncluding":"5.3","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.6.141","versionStartIncluding":"5.3","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.91","versionStartIncluding":"5.3","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.33","versionStartIncluding":"5.3","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.0.10","versionStartIncluding":"5.3","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.1","versionStartIncluding":"5.3","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnexthop: fix IPv6 route referencing IPv4 nexthop\n\nsyzbot reported a panic [1] [2].\n\nWhen an IPv6 nexthop is replaced with an IPv4 nexthop, the has_v4 flag\nof all groups containing this nexthop is not updated. This is because\nnh_group_v4_update is only called when replacing AF_INET to AF_INET6,\nbut the reverse direction (AF_INET6 to AF_INET) is missed.\n\nThis allows a stale has_v4=false to bypass fib6_check_nexthop, causing\nIPv6 routes to be attached to groups that effectively contain only AF_INET\nmembers. Subsequent route lookups then call nexthop_fib6_nh() which\nreturns NULL for the AF_INET member, leading to a NULL pointer\ndereference.\n\nFix by calling nh_group_v4_update whenever the family changes, not just\nAF_INET to AF_INET6.\n\nReproducer:\n\t# AF_INET6 blackhole\n\tip -6 nexthop add id 1 blackhole\n\t# group with has_v4=false\n\tip nexthop add id 100 group 1\n\t# replace with AF_INET (no -6), has_v4 stays false\n\tip nexthop replace id 1 blackhole\n\t# pass stale has_v4 check\n\tip -6 route add 2001:db8::/64 nhid 100\n\t# panic\n\tping -6 2001:db8::1\n\n[1] https://syzkaller.appspot.com/bug?id=e17283eb2f8dcf3dd9b47fe6f67a95f71faadad0\n[2] https://syzkaller.appspot.com/bug?id=8699b6ae54c9f35837d925686208402949e12ef3"}],"providerMetadata":{"dateUpdated":"2026-06-24T16:29:22.973Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/ceffe81a0be92afc0cd1340bc8ca46559cce9bb4"},{"url":"https://git.kernel.org/stable/c/9c2d6770a5f4545a307eb66979bef7656a34d621"},{"url":"https://git.kernel.org/stable/c/6275796f22bb382f3e9aa58ed0b4ef7bdad78cb8"},{"url":"https://git.kernel.org/stable/c/aaac3bed034239e1d75732211d9b05f30b0b4f35"},{"url":"https://git.kernel.org/stable/c/ad85961004fd4bd2f31209ac4b07612c6cefb9e7"},{"url":"https://git.kernel.org/stable/c/613c8f4a501421dd258b07ea614205d4e16ec845"},{"url":"https://git.kernel.org/stable/c/b3b7e850e1541f0520c4a12ec884255c30427ff6"},{"url":"https://git.kernel.org/stable/c/29c95185ba32b621fbc3800fb86e7dc3edf5c2be"}],"title":"nexthop: fix IPv6 route referencing IPv4 nexthop","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-53012","datePublished":"2026-06-24T16:29:22.973Z","dateReserved":"2026-06-09T07:44:35.378Z","dateUpdated":"2026-06-24T16:29:22.973Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-06-24 17:17:12","lastModifiedDate":"2026-07-10 19:24:19","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"53012","Ordinal":"1","Title":"nexthop: fix IPv6 route referencing IPv4 nexthop","CVE":"CVE-2026-53012","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"53012","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nnexthop: fix IPv6 route referencing IPv4 nexthop\n\nsyzbot reported a panic [1] [2].\n\nWhen an IPv6 nexthop is replaced with an IPv4 nexthop, the has_v4 flag\nof all groups containing this nexthop is not updated. This is because\nnh_group_v4_update is only called when replacing AF_INET to AF_INET6,\nbut the reverse direction (AF_INET6 to AF_INET) is missed.\n\nThis allows a stale has_v4=false to bypass fib6_check_nexthop, causing\nIPv6 routes to be attached to groups that effectively contain only AF_INET\nmembers. Subsequent route lookups then call nexthop_fib6_nh() which\nreturns NULL for the AF_INET member, leading to a NULL pointer\ndereference.\n\nFix by calling nh_group_v4_update whenever the family changes, not just\nAF_INET to AF_INET6.\n\nReproducer:\n\t# AF_INET6 blackhole\n\tip -6 nexthop add id 1 blackhole\n\t# group with has_v4=false\n\tip nexthop add id 100 group 1\n\t# replace with AF_INET (no -6), has_v4 stays false\n\tip nexthop replace id 1 blackhole\n\t# pass stale has_v4 check\n\tip -6 route add 2001:db8::/64 nhid 100\n\t# panic\n\tping -6 2001:db8::1\n\n[1] https://syzkaller.appspot.com/bug?id=e17283eb2f8dcf3dd9b47fe6f67a95f71faadad0\n[2] https://syzkaller.appspot.com/bug?id=8699b6ae54c9f35837d925686208402949e12ef3","Type":"Description","Title":"nexthop: fix IPv6 route referencing IPv4 nexthop"}]}}}