{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2023-53477", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-10-01T11:39:39.401Z", "datePublished": "2025-10-01T11:42:46.279Z", "dateUpdated": "2026-05-11T19:45:44.688Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-05-11T19:45:44.688Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nipv6: Add lwtunnel encap size of all siblings in nexthop calculation\n\nIn function rt6_nlmsg_size(), the length of nexthop is calculated\nby multipling the nexthop length of fib6_info and the number of\nsiblings. However if the fib6_info has no lwtunnel but the siblings\nhave lwtunnels, the nexthop length is less than it should be, and\nit will trigger a warning in inet6_rt_notify() as follows:\n\nWARNING: CPU: 0 PID: 6082 at net/ipv6/route.c:6180 inet6_rt_notify+0x120/0x130\n......\nCall Trace:\n \n fib6_add_rt2node+0x685/0xa30\n fib6_add+0x96/0x1b0\n ip6_route_add+0x50/0xd0\n inet6_rtm_newroute+0x97/0xa0\n rtnetlink_rcv_msg+0x156/0x3d0\n netlink_rcv_skb+0x5a/0x110\n netlink_unicast+0x246/0x350\n netlink_sendmsg+0x250/0x4c0\n sock_sendmsg+0x66/0x70\n ___sys_sendmsg+0x7c/0xd0\n __sys_sendmsg+0x5d/0xb0\n do_syscall_64+0x3f/0x90\n entry_SYSCALL_64_after_hwframe+0x72/0xdc\n\nThis bug can be reproduced by script:\n\nip -6 addr add 2002::2/64 dev ens2\nip -6 route add 100::/64 via 2002::1 dev ens2 metric 100\n\nfor i in 10 20 30 40 50 60 70;\ndo\n\tip link add link ens2 name ipv_$i type ipvlan\n\tip -6 addr add 2002::$i/64 dev ipv_$i\n\tifconfig ipv_$i up\ndone\n\nfor i in 10 20 30 40 50 60;\ndo\n\tip -6 route append 100::/64 encap ip6 dst 2002::$i via 2002::1\ndev ipv_$i metric 100\ndone\n\nip -6 route append 100::/64 via 2002::1 dev ipv_70 metric 100\n\nThis patch fixes it by adding nexthop_len of every siblings using\nrt6_nh_nlmsg_size()." } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/ipv6/route.c" ], "versions": [ { "version": "beb1afac518dec5a15dc92ba8f0ca016dcf457b4", "lessThan": "aba298b35619213ca787d08d472049627d8cd012", "status": "affected", "versionType": "git" }, { "version": "beb1afac518dec5a15dc92ba8f0ca016dcf457b4", "lessThan": "da26369377f0b671c14692e2d65ceb38131053e1", "status": "affected", "versionType": "git" }, { "version": "beb1afac518dec5a15dc92ba8f0ca016dcf457b4", "lessThan": "dcdddb5f490890d058ea1f194d661219e92fe88d", "status": "affected", "versionType": "git" }, { "version": "beb1afac518dec5a15dc92ba8f0ca016dcf457b4", "lessThan": "e11e4d524eba2d3c8fdf897d7ce3853f7573bae9", "status": "affected", "versionType": "git" }, { "version": "beb1afac518dec5a15dc92ba8f0ca016dcf457b4", "lessThan": "aa75d826c221e8d48607aef33836cf872a159cf1", "status": "affected", "versionType": "git" }, { "version": "beb1afac518dec5a15dc92ba8f0ca016dcf457b4", "lessThan": "4cc59f386991ec9374cb4bc83dbe1c0b5a95033f", "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/route.c" ], "versions": [ { "version": "4.11", "status": "affected" }, { "version": "0", "lessThan": "4.11", "status": "unaffected", "versionType": "semver" }, { "version": "5.4.235", "lessThanOrEqual": "5.4.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.173", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.100", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.18", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.2.5", "lessThanOrEqual": "6.2.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.3", "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": "4.11", "versionEndExcluding": "5.4.235" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "5.10.173" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "5.15.100" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "6.1.18" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "6.2.5" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "6.3" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/aba298b35619213ca787d08d472049627d8cd012" }, { "url": "https://git.kernel.org/stable/c/da26369377f0b671c14692e2d65ceb38131053e1" }, { "url": "https://git.kernel.org/stable/c/dcdddb5f490890d058ea1f194d661219e92fe88d" }, { "url": "https://git.kernel.org/stable/c/e11e4d524eba2d3c8fdf897d7ce3853f7573bae9" }, { "url": "https://git.kernel.org/stable/c/aa75d826c221e8d48607aef33836cf872a159cf1" }, { "url": "https://git.kernel.org/stable/c/4cc59f386991ec9374cb4bc83dbe1c0b5a95033f" } ], "title": "ipv6: Add lwtunnel encap size of all siblings in nexthop calculation", "x_generator": { "engine": "bippy-1.2.0" } } } }