{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-64542", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-07-19T15:36:31.795Z", "datePublished": "2026-07-27T20:10:34.994Z", "dateUpdated": "2026-07-27T20:10:34.994Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-07-27T20:10:34.994Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nipv6: ndisc: fix NULL deref in accept_untracked_na()\n\naccept_untracked_na() re-fetches the inet6_dev with __in6_dev_get(dev)\nand dereferences idev->cnf.accept_untracked_na without a NULL check,\neven though its only caller ndisc_recv_na() already fetched and\nNULL-checked idev for the same device.\n\nBoth reads of dev->ip6_ptr run in the same RCU read-side critical\nsection, but a concurrent addrconf_ifdown() can clear dev->ip6_ptr\nbetween them: lowering the MTU below IPV6_MIN_MTU calls addrconf_ifdown()\nwithout the synchronize_net() that orders the unregister path, so the\nre-fetch returns NULL and oopses:\n\n BUG: KASAN: null-ptr-deref in ndisc_recv_na (net/ipv6/ndisc.c:974)\n Read of size 4 at addr 0000000000000364\n Call Trace:\n <IRQ>\n ndisc_recv_na (net/ipv6/ndisc.c:974)\n icmpv6_rcv (net/ipv6/icmp.c:1193)\n ip6_protocol_deliver_rcu (net/ipv6/ip6_input.c:479)\n ip6_input_finish (net/ipv6/ip6_input.c:534)\n ip6_input (net/ipv6/ip6_input.c:545)\n ip6_mc_input (net/ipv6/ip6_input.c:635)\n ipv6_rcv (net/ipv6/ip6_input.c:351)\n </IRQ>\n\nIt is reachable by an unprivileged user via a network namespace.\n\nPass the caller's already validated idev instead of re-fetching it; the\nidev stays alive for the whole RCU critical section, so it is safe even\nafter dev->ip6_ptr has been cleared."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/ipv6/ndisc.c"], "versions": [{"version": "aaa5f515b16b6b3e137779ffb4c9558bb58c1e75", "lessThan": "62c719203cb521b64fab74da94a81bdde5c18808", "status": "affected", "versionType": "git"}, {"version": "aaa5f515b16b6b3e137779ffb4c9558bb58c1e75", "lessThan": "a6450f7cfae57b382cbaf66a577765c9a88b3c58", "status": "affected", "versionType": "git"}, {"version": "aaa5f515b16b6b3e137779ffb4c9558bb58c1e75", "lessThan": "63d1c23764de2309cedbb779c75188d257a09d9b", "status": "affected", "versionType": "git"}, {"version": "aaa5f515b16b6b3e137779ffb4c9558bb58c1e75", "lessThan": "d186e942365acece7c56d39da05dd63bf95b280a", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/ipv6/ndisc.c"], "versions": [{"version": "6.0", "status": "affected"}, {"version": "0", "lessThan": "6.0", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.97", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.40", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.1.5", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2-rc1", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.0", "versionEndExcluding": "6.12.97"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.0", "versionEndExcluding": "6.18.40"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.0", "versionEndExcluding": "7.1.5"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.0", "versionEndExcluding": "7.2-rc1"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/62c719203cb521b64fab74da94a81bdde5c18808"}, {"url": "https://git.kernel.org/stable/c/a6450f7cfae57b382cbaf66a577765c9a88b3c58"}, {"url": "https://git.kernel.org/stable/c/63d1c23764de2309cedbb779c75188d257a09d9b"}, {"url": "https://git.kernel.org/stable/c/d186e942365acece7c56d39da05dd63bf95b280a"}], "title": "ipv6: ndisc: fix NULL deref in accept_untracked_na()", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[aaa5f515b16b6b3e137779ffb4c9558bb58c1e75,62c719203cb521b64fab74da94a81bdde5c18808)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[aaa5f515b16b6b3e137779ffb4c9558bb58c1e75,a6450f7cfae57b382cbaf66a577765c9a88b3c58)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[aaa5f515b16b6b3e137779ffb4c9558bb58c1e75,63d1c23764de2309cedbb779c75188d257a09d9b)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[aaa5f515b16b6b3e137779ffb4c9558bb58c1e75,d186e942365acece7c56d39da05dd63bf95b280a)"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "6.0"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,6.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.12.97,6.13.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.40,6.19.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.1.5,7.2.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.2-rc1,*]"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "created": "2026-07-28T02:15:17.609442+00:00", "updated": "2026-07-28T02:15:17.609474+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}