{ "schemaVersion": 1, "attribution": [ { "source": "CISA Known Exploited Vulnerabilities", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog", "licence": "US government work" }, { "source": "GitHub Advisory Database", "url": "https://github.com/advisories", "licence": "CC BY 4.0" }, { "source": "Have I Been Pwned", "url": "https://haveibeenpwned.com/", "licence": "CC BY 4.0" }, { "source": "CVE Program (CVE records)", "url": "https://www.cve.org/Legal/TermsOfUse", "licence": "CVE Terms of Use", "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.", "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy." }, { "source": "FIRST EPSS", "url": "https://www.first.org/epss/", "licence": "free to use; FIRST requests attribution" } ], "record": { "id": "CVE-2026-64114", "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-64114", "idYear": 2026, "status": "PUBLISHED", "publishedAt": "2026-07-19T15:40:14.854Z", "updatedAt": "2026-10-19T20:28:12.671Z", "importedAt": "2026-10-24T01:58:25.636Z", "snapshot": { "id": "cve_2026-10-24_midnight_baseline", "at": "2026-10-24T00:00:00.000Z", "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z" }, "facts": { "title": "ipv4: raw: reject IP_HDRINCL packets with ihl < 5", "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nipv4: raw: reject IP_HDRINCL packets with ihl < 5\n\nraw_send_hdrinc() validates that the caller-supplied IPv4 header\nfits within the message length:\n\n iphlen = iph->ihl * 4;\n err = -EINVAL;\n if (iphlen > length)\n goto error_free;\n\n if (iphlen >= sizeof(*iph)) {\n /* fix up saddr, tot_len, id, csum, transport_header */\n }\n\nIt does not, however, reject ihl < 5. For such a packet the\n\"if (iphlen >= sizeof(*iph))\" branch is skipped, leaving the\ncrafted iphdr untouched, but the packet is still handed to\n__ip_local_out() and onward. Downstream consumers that read\niph->ihl assume a sane value: net/ipv4/ah4.c:ah_output() in\nparticular subtracts sizeof(struct iphdr) from top_iph->ihl * 4\nand passes the (signed-int-negative, then cast to size_t)\nresult to memcpy(), producing an OOB access of length close to\nSIZE_MAX and a host kernel panic.\n\nAn IPv4 header with ihl < 5 is malformed by definition (RFC 791:\n\"Internet Header Length is the length of the internet header in\n32 bit words ... Note that the minimum value for a correct header\nis 5.\"). The kernel should not be willing to inject such a\npacket into its own output path.\n\nReject \"iphlen < sizeof(*iph)\" alongside the existing\n\"iphlen > length\" check. This matches the principle that locally\nconstructed packets that re-enter the IP stack must pass the same\nbasic sanity tests that a foreign packet would be subjected to.\n\nOnce this lands, the \"if (iphlen >= sizeof(*iph))\" wrapper around\nthe fixup branch becomes redundant; left in place to keep the\npatch minimal and backport-friendly. A follow-up can unwrap it.\n\nNote that commit 86f4c90a1c5c (\"ipv4, ipv6: ensure raw socket\nmessage is big enough to hold an IP header\") ensures the message\nbuffer is large enough to hold an iphdr, but does not constrain\nthe self-reported iph->ihl.\n\nReachability: the malformed packet source is any caller with\nCAP_NET_RAW, including an unprivileged process in a user+net\nnamespace on a kernel with CONFIG_USER_NS=y. The reproduced AH\ncrash also requires a matching xfrm AH policy on the outgoing\nroute; a container granted CAP_NET_ADMIN can install that state\nand policy in its netns. Loopback bypasses xfrm_output, so the\ntrigger uses a real netdev.\n\nReproduced on UML + KASAN: kernel-mode fault at addr 0x0 with\nmemcpy_orig at the crash site. Same shape reproduces inside a\nrootless Docker container with --cap-add NET_ADMIN on a stock\ndistro kernel.", "affected": [ { "vendor": "Linux", "product": "Linux", "defaultStatus": "unaffected", "versions": [ { "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "status": "affected", "versionType": "git", "lessThan": "1065b9efa4126df559b03a849c139ecfae92cd25" }, { "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "status": "affected", "versionType": "git", "lessThan": "bc20dbd48c26e743f7e0845020c11ed2ce8b15ee" }, { "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "status": "affected", "versionType": "git", "lessThan": "5a564f737ec54d63e8ee221d3ff396d07586d464" }, { "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "status": "affected", "versionType": "git", "lessThan": "3c5411fa4944ed99af3d9d1de750ea8169b6dac9" }, { "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "status": "affected", "versionType": "git", "lessThan": "145e9afa5b905229b4788bb72c3255f5a5f77508" }, { "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "status": "affected", "versionType": "git", "lessThan": "7725cd3b471740fd23d25ed1da722c671fb2a5d3" }, { "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "status": "affected", "versionType": "git", "lessThan": "bbe0be67de296176e7243c76e3d9f02f6ae9ff0b" }, { "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "status": "affected", "versionType": "git", "lessThan": "915fab69823a14c170dbaa3b41978768e0fe62fc" } ] }, { "vendor": "Linux", "product": "Linux", "defaultStatus": "affected", "versions": [ { "version": "2.6.12", "status": "affected" }, { "version": "0", "status": "unaffected", "versionType": "semver", "lessThan": "2.6.12" }, { "version": "5.10.258", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.10.*" }, { "version": "5.15.209", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.15.*" }, { "version": "6.1.175", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.1.*" }, { "version": "6.6.142", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.6.*" }, { "version": "6.12.92", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.12.*" }, { "version": "6.18.34", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.18.*" }, { "version": "7.0.11", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "7.0.*" }, { "version": "7.1", "status": "unaffected", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*" } ] } ] } } }