{ "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-2026-45840", "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-45840", "idYear": 2026, "status": "PUBLISHED", "publishedAt": "2026-05-27T09:24:39.478Z", "updatedAt": "2026-10-15T01:19:42.649Z", "importedAt": "2026-10-24T01:58:14.884Z", "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": "openvswitch: cap upcall PID array size and pre-size vport replies", "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nopenvswitch: cap upcall PID array size and pre-size vport replies\n\nThe vport netlink reply helpers allocate a fixed-size skb with\nnlmsg_new(NLMSG_DEFAULT_SIZE, ...) but serialize the full upcall PID\narray via ovs_vport_get_upcall_portids(). Since\novs_vport_set_upcall_portids() accepts any non-zero multiple of\nsizeof(u32) with no upper bound, a CAP_NET_ADMIN user can install a PID\narray large enough to overflow the reply buffer, causing nla_put() to\nfail with -EMSGSIZE and hitting BUG_ON(err < 0). On systems with\nunprivileged user namespaces enabled (e.g., Ubuntu default), this is\nreachable via unshare -Urn since OVS vport mutation operations use\nGENL_UNS_ADMIN_PERM.\n\n kernel BUG at net/openvswitch/datapath.c:2414!\n Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI\n CPU: 1 UID: 0 PID: 65 Comm: poc Not tainted 7.0.0-rc7-00195-geb216e422044 #1\n RIP: 0010:ovs_vport_cmd_set+0x34c/0x400\n Call Trace:\n \n genl_family_rcv_msg_doit (net/netlink/genetlink.c:1116)\n genl_rcv_msg (net/netlink/genetlink.c:1194)\n netlink_rcv_skb (net/netlink/af_netlink.c:2550)\n genl_rcv (net/netlink/genetlink.c:1219)\n netlink_unicast (net/netlink/af_netlink.c:1344)\n netlink_sendmsg (net/netlink/af_netlink.c:1894)\n __sys_sendto (net/socket.c:2206)\n __x64_sys_sendto (net/socket.c:2209)\n do_syscall_64 (arch/x86/entry/syscall_64.c:63)\n entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)\n \n Kernel panic - not syncing: Fatal exception\n\nReject attempts to set more PIDs than nr_cpu_ids in\novs_vport_set_upcall_portids(), and pre-compute the worst-case reply\nsize in ovs_vport_cmd_msg_size() based on that bound, similar to the\nexisting ovs_dp_cmd_msg_size(). nr_cpu_ids matches the cap already\nused by the per-CPU dispatch configuration on the datapath side\n(ovs_dp_cmd_fill_info() serialises at most nr_cpu_ids PIDs), so the\ntwo sides stay consistent.", "affected": [ { "vendor": "Linux", "product": "Linux", "defaultStatus": "unaffected", "versions": [ { "version": "5cd667b0a4567048bb555927d6ee564f4e5620a9", "status": "affected", "versionType": "git", "lessThan": "8d59b80e69dddb665eb2de36e62859ab2073470e" }, { "version": "5cd667b0a4567048bb555927d6ee564f4e5620a9", "status": "affected", "versionType": "git", "lessThan": "d9e47e29aacb9f8a9d59feb6ab5b128a9bbb40b0" }, { "version": "5cd667b0a4567048bb555927d6ee564f4e5620a9", "status": "affected", "versionType": "git", "lessThan": "b39f763d720d623218bc1d95ace6855d7b474e81" }, { "version": "5cd667b0a4567048bb555927d6ee564f4e5620a9", "status": "affected", "versionType": "git", "lessThan": "f9ef3db77a383d66847fd082c2b437d8ae4d9c63" }, { "version": "5cd667b0a4567048bb555927d6ee564f4e5620a9", "status": "affected", "versionType": "git", "lessThan": "f99ac36b5d7c719d08a69fcdecce40f78a874e15" }, { "version": "5cd667b0a4567048bb555927d6ee564f4e5620a9", "status": "affected", "versionType": "git", "lessThan": "fa6e90bc443bed8dc0d55bc5ea5b27ffdfe37704" }, { "version": "5cd667b0a4567048bb555927d6ee564f4e5620a9", "status": "affected", "versionType": "git", "lessThan": "1d6c02b86329883aa467a3a61f8d34369db73a2f" }, { "version": "5cd667b0a4567048bb555927d6ee564f4e5620a9", "status": "affected", "versionType": "git", "lessThan": "2091c6aa0df6aba47deb5c8ab232b1cb60af3519" } ] }, { "vendor": "Linux", "product": "Linux", "defaultStatus": "affected", "versions": [ { "version": "3.17", "status": "affected" }, { "version": "0", "status": "unaffected", "versionType": "semver", "lessThan": "3.17" }, { "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": "6.6.141", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.6.*" }, { "version": "6.12.91", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.12.*" }, { "version": "6.18.33", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.18.*" }, { "version": "7.0.10", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "7.0.*" }, { "version": "7.1", "status": "unaffected", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*" } ] } ] } } }