{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-98485", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-25T10:25:14.352Z", "datePublished": "2026-10-18T15:16:00.435Z", "dateUpdated": "2026-10-24T14:09:02.897Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-24T14:09:02.897Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: ip6t_rt: fix zero-address non-strict match out-of-bounds read\n\nrt_mt6_check() permits rules to be configured with rtinfo->addrnr == 0\neven when address matching (IP6T_RT_FST_MASK) is requested.\n\nIn the IP6T_RT_FST_NSTRICT path, rt_mt6() evaluates packet routing\naddresses against rtinfo->addrs[i] and terminates backwards at the bottom\nof the loop:\n\n if (ipv6_addr_equal(ap, &rtinfo->addrs[i])) {\n i++;\n }\n if (i == rtinfo->addrnr)\n break;\n\nWhen addrnr is 0, if the first packet address matches rtinfo->addrs[0],\ni is incremented to 1. Because i is now strictly greater than addrnr (0),\nthe loop termination condition (i == rtinfo->addrnr) is bypassed and will\nnever be satisfied.\n\nIf a crafted IPv6 packet contains matching routing addresses, i will\nadvance past IP6T_RT_HOPS (16). The subsequent call to ipv6_addr_equal()\nreads beyond struct ip6t_rt, triggering UBSAN/KASAN out-of-bounds warnings\nor kernel panics.\n\nFix this by:\n1. Rejecting rules in rt_mt6_check() where IP6T_RT_FST_MASK is set but\n rtinfo->addrnr is zero.\n2. In rt_mt6(), moving the termination condition (i < rtinfo->addrnr)\n into the for-loop header condition and removing the backwards break\n at the end of the loop body." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H", "baseScore": 7.1, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The bad state enters through local setsockopt(IP6T_SO_SET_REPLACE) or NFT_MSG_NEWRULE rule installation; ip6_rcv then reaches rt_mt6 through NF_INET_PRE_ROUTING and ip6t_do_table. A remote packet alone cannot create the required zero-address rule.\nAC:L - The attacker controls the rule's addrs[] despite addrnr being zero and can send a 17-address routing header whose first 16 addresses match, making rt_mt6 deterministically read addrs[16]. No race or external timing condition is required.\nPR:L - do_ip6t_set_ctl requires ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN), while nfnetlink uses netlink_net_capable; an unprivileged user can satisfy either check in a user-created user and network namespace.\nUI:N - The attacker installs the malformed rule and injects the triggering IPv6 packet through their own syscalls. No action by another user is needed.\nS:U - The invalid read occurs during netfilter rule evaluation inside the same host kernel security authority. It does not cross a VM, IOMMU, or comparable scope boundary.\nC:H - ipv6_addr_equal() reads 16 bytes from each selected &rtinfo->addrs[i], and rt_mt6 can advance beyond the fixed 16-entry array across up to 127 routing-header address iterations. The overread is therefore not strictly bounded to a few bytes.\nI:N - rt_mt6 only fetches the out-of-bounds address for comparison and updates its local index; it performs no out-of-bounds write or other memory modification.\nA:H - At i == 16, the fixed-array subscript and 16-byte ipv6_addr_equal() load trigger UBSAN/KASAN out-of-bounds handling and can panic the kernel, as documented by the fix. The attacker can repeat the rule-and-packet sequence without a race." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/ipv6/netfilter/ip6t_rt.c" ], "versions": [ { "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "959d1829d1ce8b91b435b24a923b51bcc8897090", "status": "affected", "versionType": "git" }, { "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "fe336bab13834394320997de8b16ca4a913b4f13", "status": "affected", "versionType": "git" }, { "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "5a54f8b7f7fe207a5c14713015a5820588faf1ad", "status": "affected", "versionType": "git" }, { "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "b89249819a7d6698bed152feafd3bc6c08489d15", "status": "affected", "versionType": "git" }, { "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "dd55c0ea87bf70e4e4b3b683acd29ef981335b26", "status": "affected", "versionType": "git" }, { "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "191239b0939692e92459d8d32cad14247fa93f89", "status": "affected", "versionType": "git" }, { "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "d9cf4ac6f326330e1fe4d95671d36a6ff3593f64", "status": "affected", "versionType": "git" }, { "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "82313c169eddc02b1bf5ba6b427803e272d3ec42", "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/netfilter/ip6t_rt.c" ], "versions": [ { "version": "2.6.12", "status": "affected" }, { "version": "0", "lessThan": "2.6.12", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.271", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.222", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.189", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.158", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.112", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.55", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2.9", "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": "2.6.12", "versionEndExcluding": "5.10.271" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.12", "versionEndExcluding": "5.15.222" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.12", "versionEndExcluding": "6.1.189" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.12", "versionEndExcluding": "6.6.158" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.12", "versionEndExcluding": "6.12.112" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.12", "versionEndExcluding": "6.18.55" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.12", "versionEndExcluding": "7.2.9" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.12", "versionEndExcluding": "7.3" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/959d1829d1ce8b91b435b24a923b51bcc8897090" }, { "url": "https://git.kernel.org/stable/c/fe336bab13834394320997de8b16ca4a913b4f13" }, { "url": "https://git.kernel.org/stable/c/5a54f8b7f7fe207a5c14713015a5820588faf1ad" }, { "url": "https://git.kernel.org/stable/c/b89249819a7d6698bed152feafd3bc6c08489d15" }, { "url": "https://git.kernel.org/stable/c/dd55c0ea87bf70e4e4b3b683acd29ef981335b26" }, { "url": "https://git.kernel.org/stable/c/191239b0939692e92459d8d32cad14247fa93f89" }, { "url": "https://git.kernel.org/stable/c/d9cf4ac6f326330e1fe4d95671d36a6ff3593f64" }, { "url": "https://git.kernel.org/stable/c/82313c169eddc02b1bf5ba6b427803e272d3ec42" } ], "title": "netfilter: ip6t_rt: fix zero-address non-strict match out-of-bounds read", "x_generator": { "engine": "bippy-1.2.0" } } } }