{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-99064", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-25T10:25:14.389Z", "datePublished": "2026-10-23T12:23:05.854Z", "dateUpdated": "2026-10-24T14:10:17.979Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-24T14:10:17.979Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncipso: adjust cached option offsets when removing CIPSO\n\ncipso_v4_skbuff_delattr() removes the CIPSO bytes but does not adjust\ncached offsets for options that follow them.\n\nFor example, with a valid 10-byte CIPSO option followed by a seven-byte\nRR option, parsing records rr at offset 30. Removing CIPSO moves RR to\noffset 20, while the cached offset remains 30. Consumers such as\nip_forward_options() and __ip_options_echo() then access the wrong bytes;\nthe latter may interpret packet data as the option length and copy it into\nfixed-size option storage.\n\nMirror cipso_v4_delopt() and subtract cipso_len from the srr, rr, ts and\nrouter_alert offsets when they follow CIPSO. cipso_len is the distance\nthe first memmove() shifts those options. The later header move and\nnetwork-header reset relocate the bytes and their offset base together." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 8.1, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:N - A remote peer can send an IPv4 datagram containing valid CIPSO followed by RR/TS; ip_rcv()->ip_rcv_options() caches their wire offsets, then selinux_ip_forward()->netlbl_skbuff_setattr()->cipso_v4_skbuff_delattr() removes CIPSO without rebasing them.\nAC:H - The strongest path requires a CONFIG_NETLABEL/SELinux forwarding gateway with network_peer_controls, a recognized CIPSO DOI, an UNLABELED egress mapping, and a later FORWARD REJECT invoking nf_send_unreach(); these non-default conditions are outside the sender's control.\nPR:N - __ip_options_compile() applies CAP_NET_RAW only when skb is NULL; received packets undergo cipso_v4_validate() and SELinux label-policy checks, but require no peer authentication, victim credentials, or target-side privileges.\nUI:N - After the datagram arrives, ip_rcv(), SELinux FORWARD relabeling, and nf_send_unreach()->__ip_options_echo() execute entirely in kernel packet handling without any victim action.\nS:U - The overwrite occurs in __ip_options_echo()'s in-kernel reply-option storage and can compromise the same host kernel; it crosses no VM, IOMMU, or separate security-authority boundary.\nC:H - With stale opt->rr pointing into payload, __ip_options_echo() takes an attacker-chosen length and source bytes and copies up to 255 bytes into 40-byte replyopts.opt.__data; control-flow compromise from this stack overwrite can expose arbitrary kernel memory.\nI:H - The memcpy() can place 255 attacker-controlled payload bytes into the 40-byte stack destination, crossing the stack canary and saved return address in the demonstrated x86-64 layout and enabling kernel control-flow hijacking.\nA:H - The 255-byte __ip_options_echo() stack overwrite triggers KASAN or the stack canary and can panic the kernel; the packet-processing path can be invoked repeatedly with crafted IPv4 datagrams." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/ipv4/cipso_ipv4.c" ], "versions": [ { "version": "89aa3619d141d6cfb6040a561aebb6d99d3e2285", "lessThan": "b965977126a90e01825814c859ba4788691eddd3", "status": "affected", "versionType": "git" }, { "version": "89aa3619d141d6cfb6040a561aebb6d99d3e2285", "lessThan": "2200fe1d6148b78e1b8f00f4b2bd47760015077f", "status": "affected", "versionType": "git" }, { "version": "89aa3619d141d6cfb6040a561aebb6d99d3e2285", "lessThan": "6e49d611a9cfbaac927b8fa80ebd4f6b1f37ada0", "status": "affected", "versionType": "git" }, { "version": "89aa3619d141d6cfb6040a561aebb6d99d3e2285", "lessThan": "6d25ffca055a77787c21a36b66c253f76239411b", "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/ipv4/cipso_ipv4.c" ], "versions": [ { "version": "6.10", "status": "affected" }, { "version": "0", "lessThan": "6.10", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.113", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.57", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2.11", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.3", "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": "6.10", "versionEndExcluding": "6.12.113" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.10", "versionEndExcluding": "6.18.57" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.10", "versionEndExcluding": "7.2.11" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.10", "versionEndExcluding": "7.3" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/b965977126a90e01825814c859ba4788691eddd3" }, { "url": "https://git.kernel.org/stable/c/2200fe1d6148b78e1b8f00f4b2bd47760015077f" }, { "url": "https://git.kernel.org/stable/c/6e49d611a9cfbaac927b8fa80ebd4f6b1f37ada0" }, { "url": "https://git.kernel.org/stable/c/6d25ffca055a77787c21a36b66c253f76239411b" } ], "title": "cipso: adjust cached option offsets when removing CIPSO", "x_generator": { "engine": "bippy-1.2.0" } } } }