{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-98532", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-25T10:25:14.355Z", "datePublished": "2026-10-18T15:17:50.490Z", "dateUpdated": "2026-10-24T14:09:19.064Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-24T14:09:19.064Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nipv6: do not let ipv6_find_hdr() return an offset past the packet end\n\nipv6_find_hdr() walks the extension header chain, skipping each header by\nthe length that header itself declares. ipv6_optlen() returns up to 2048,\nand the skip is never checked against skb->len, so the offset stored in\n*offset can point past the end of the packet.\n\nopenvswitch installs that offset as the transport header, and\nupdate_ipv6_checksum() then reads and writes the transport checksum field\nout of bounds:\n\n BUG: KASAN: slab-use-after-free in inet_proto_csum_replace16+0x445/0x470\n Read of size 2 at addr ffff88810b754b06 by task ovs_ipv6_oob/629\n CPU: 4 UID: 1000 PID: 629 Comm: ovs_ipv6_oob Tainted: G N 7.3.0-rc3+ #348\n Call Trace:\n inet_proto_csum_replace16+0x445/0x470\n set_ipv6_addr+0x3dd/0x460\n do_execute_actions+0x6a3d/0x7c40\n ovs_execute_actions+0xfd/0x480\n ovs_packet_cmd_execute+0xc38/0xf20\n genl_rcv_msg+0x59e/0x870\n netlink_rcv_skb+0x18b/0x450\n genl_rcv+0x2d/0x40\n netlink_unicast+0x6bc/0xa20\n\n The buggy address belongs to the object at ffff88810b754980\n which belongs to the cache skbuff_small_head of size 704\n The buggy address is located 390 bytes inside of\n freed 704-byte region [ffff88810b754980, ffff88810b754c40)\n\nOther callers use that offset too, so bound it here rather than in one\ncaller.\n\nReject a header whose declared length does not fit in the packet.\nipv6_find_hdr() already fails with -EBADMSG on a malformed chain, so this\nadds no new failure mode." } ], "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 routed IPv6 datagram can carry a short Destination Options header whose hdrlen declares up to 2048 bytes; __netif_receive_skb_core() -> netdev_frame_hook() -> ovs_vport_receive() -> parse_ipv6hdr() reaches the patched ipv6_find_hdr(), which returns a transport offset beyond skb->len.\nAC:H - Corruption requires the packet to match a preinstalled OVS_ACTION_ATTR_SET_MASKED IPv6 address-rewrite action that changes an address; although the sender controls nexthdr and hdrlen, that capability-gated datapath state is outside a remote attacker's control.\nPR:N - netdev_frame_hook() and ovs_vport_receive() process matching received packets without authentication or capability checks; GENL_UNS_ADMIN_PERM protects installation of the OVS flow, not the remote sender triggering it.\nUI:N - Once the affected OVS rewrite flow exists, packet receipt automatically runs parse_ipv6hdr(), ovs_dp_process_packet(), and set_ipv6_addr() without any victim action.\nS:U - The bad offset from ipv6_find_hdr() and the resulting skbuff corruption occur within the same host kernel networking security authority; this is ordinary in-kernel compromise rather than a boundary-enforcement bypass.\nC:H - inet_proto_csum_replace16() reads the attacker-selected out-of-range 16-bit location before rewriting it; hdrlen can place this access in adjacent or reclaimed skbuff_small_head storage, where corrupting skb pointer or length metadata can enable broader kernel-memory disclosure.\nI:H - inet_proto_csum_replace16() stores through tcp_hdr(), udp_hdr(), or icmp6_hdr() at the unchecked transport offset; hdrlen selects a location up to roughly 2 KiB past the packet and the IPv6 address delta controls the 16-bit modification, yielding an exploitable heap-write primitive.\nA:H - The demonstrated set_ipv6_addr() path produced a KASAN slab-use-after-free in inet_proto_csum_replace16(); repeated matching packets can corrupt adjacent skb storage and cause a kernel oops or panic." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/ipv6/exthdrs_core.c" ], "versions": [ { "version": "f8f626754ebeca613cf1af2e6f890cfde0e74d5b", "lessThan": "ca96b38730e31357ef4a9d76af1336958ac670d7", "status": "affected", "versionType": "git" }, { "version": "f8f626754ebeca613cf1af2e6f890cfde0e74d5b", "lessThan": "531255de8971c06d5d5986f85fdc2525d707ba71", "status": "affected", "versionType": "git" }, { "version": "f8f626754ebeca613cf1af2e6f890cfde0e74d5b", "lessThan": "543354c6efb27eae3372a3a9674aeaa2a86e2b2c", "status": "affected", "versionType": "git" }, { "version": "f8f626754ebeca613cf1af2e6f890cfde0e74d5b", "lessThan": "dc92cb972e86790b8078337ec41015b748b8f8e5", "status": "affected", "versionType": "git" }, { "version": "f8f626754ebeca613cf1af2e6f890cfde0e74d5b", "lessThan": "1c70275ca87e769e1a52abc644d61372d8c016cb", "status": "affected", "versionType": "git" }, { "version": "f8f626754ebeca613cf1af2e6f890cfde0e74d5b", "lessThan": "1d42828565889632068fbc2983c34d57c66af4e0", "status": "affected", "versionType": "git" }, { "version": "f8f626754ebeca613cf1af2e6f890cfde0e74d5b", "lessThan": "4254d5878c320c19961dd0b8e1d0aca4800d8b7d", "status": "affected", "versionType": "git" }, { "version": "f8f626754ebeca613cf1af2e6f890cfde0e74d5b", "lessThan": "ee319bd3a0e976af5087cbe59ebc50a66f31d202", "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/exthdrs_core.c" ], "versions": [ { "version": "3.8", "status": "affected" }, { "version": "0", "lessThan": "3.8", "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": "3.8", "versionEndExcluding": "5.10.271" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.8", "versionEndExcluding": "5.15.222" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.8", "versionEndExcluding": "6.1.189" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.8", "versionEndExcluding": "6.6.158" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.8", "versionEndExcluding": "6.12.112" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.8", "versionEndExcluding": "6.18.55" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.8", "versionEndExcluding": "7.2.9" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.8", "versionEndExcluding": "7.3" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/ca96b38730e31357ef4a9d76af1336958ac670d7" }, { "url": "https://git.kernel.org/stable/c/531255de8971c06d5d5986f85fdc2525d707ba71" }, { "url": "https://git.kernel.org/stable/c/543354c6efb27eae3372a3a9674aeaa2a86e2b2c" }, { "url": "https://git.kernel.org/stable/c/dc92cb972e86790b8078337ec41015b748b8f8e5" }, { "url": "https://git.kernel.org/stable/c/1c70275ca87e769e1a52abc644d61372d8c016cb" }, { "url": "https://git.kernel.org/stable/c/1d42828565889632068fbc2983c34d57c66af4e0" }, { "url": "https://git.kernel.org/stable/c/4254d5878c320c19961dd0b8e1d0aca4800d8b7d" }, { "url": "https://git.kernel.org/stable/c/ee319bd3a0e976af5087cbe59ebc50a66f31d202" } ], "title": "ipv6: do not let ipv6_find_hdr() return an offset past the packet end", "x_generator": { "engine": "bippy-1.2.0" } } } }