{"affected":[{"defaultStatus":"unaffected","product":"Linux","source":"CNA: Linux","vendor":"Linux","versions":[{"lessThan":"8d59b80e69dddb665eb2de36e62859ab2073470e","status":"affected","version":"5cd667b0a4567048bb555927d6ee564f4e5620a9","versionType":"git"},{"lessThan":"d9e47e29aacb9f8a9d59feb6ab5b128a9bbb40b0","status":"affected","version":"5cd667b0a4567048bb555927d6ee564f4e5620a9","versionType":"git"},{"lessThan":"b39f763d720d623218bc1d95ace6855d7b474e81","status":"affected","version":"5cd667b0a4567048bb555927d6ee564f4e5620a9","versionType":"git"},{"lessThan":"f9ef3db77a383d66847fd082c2b437d8ae4d9c63","status":"affected","version":"5cd667b0a4567048bb555927d6ee564f4e5620a9","versionType":"git"},{"lessThan":"f99ac36b5d7c719d08a69fcdecce40f78a874e15","status":"affected","version":"5cd667b0a4567048bb555927d6ee564f4e5620a9","versionType":"git"},{"lessThan":"fa6e90bc443bed8dc0d55bc5ea5b27ffdfe37704","status":"affected","version":"5cd667b0a4567048bb555927d6ee564f4e5620a9","versionType":"git"},{"lessThan":"1d6c02b86329883aa467a3a61f8d34369db73a2f","status":"affected","version":"5cd667b0a4567048bb555927d6ee564f4e5620a9","versionType":"git"},{"lessThan":"2091c6aa0df6aba47deb5c8ab232b1cb60af3519","status":"affected","version":"5cd667b0a4567048bb555927d6ee564f4e5620a9","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","source":"CNA: Linux","vendor":"Linux","versions":[{"status":"affected","version":"3.17"},{"lessThan":"3.17","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"5.10.*","status":"unaffected","version":"5.10.258","versionType":"semver"},{"lessThanOrEqual":"5.15.*","status":"unaffected","version":"5.15.209","versionType":"semver"},{"lessThanOrEqual":"6.1.*","status":"unaffected","version":"6.1.175","versionType":"semver"},{"lessThanOrEqual":"6.6.*","status":"unaffected","version":"6.6.141","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.91","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.33","versionType":"semver"},{"lessThanOrEqual":"7.0.*","status":"unaffected","version":"7.0.10","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.1","versionType":"original_commit_for_fix"}]},{"defaultStatus":"unknown","product":"SIMATIC S7-1500 TM MFP - GNU/Linux subsystem","source":"ADP: siemens-SADP","vendor":"Siemens","versions":[{"lessThan":"*","status":"affected","version":"0","versionType":"custom"}]}],"cveId":"CVE-2026-45840","cwes":[],"description":"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  <TASK>\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  </TASK>\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.","epss":{"date":"2026-11-06","percentile":0.028,"score":0.00132},"exploits":[],"kev":null,"metrics":[],"modifiedAt":1793979778715,"publishedAt":1779873879478,"references":[{"source":"CNA: Linux","tags":[],"url":"https://git.kernel.org/stable/c/8d59b80e69dddb665eb2de36e62859ab2073470e"},{"source":"CNA: Linux","tags":[],"url":"https://git.kernel.org/stable/c/d9e47e29aacb9f8a9d59feb6ab5b128a9bbb40b0"},{"source":"CNA: Linux","tags":[],"url":"https://git.kernel.org/stable/c/b39f763d720d623218bc1d95ace6855d7b474e81"},{"source":"CNA: Linux","tags":[],"url":"https://git.kernel.org/stable/c/f9ef3db77a383d66847fd082c2b437d8ae4d9c63"},{"source":"CNA: Linux","tags":[],"url":"https://git.kernel.org/stable/c/f99ac36b5d7c719d08a69fcdecce40f78a874e15"},{"source":"CNA: Linux","tags":[],"url":"https://git.kernel.org/stable/c/fa6e90bc443bed8dc0d55bc5ea5b27ffdfe37704"},{"source":"CNA: Linux","tags":[],"url":"https://git.kernel.org/stable/c/1d6c02b86329883aa467a3a61f8d34369db73a2f"},{"source":"CNA: Linux","tags":[],"url":"https://git.kernel.org/stable/c/2091c6aa0df6aba47deb5c8ab232b1cb60af3519"},{"source":"ADP: siemens-SADP","tags":[],"url":"https://cert-portal.siemens.com/productcert/html/ssa-784472.html"}],"remediation":[],"revision":"77e23c0c003bee4179a75674fe2337a462ce0eed0b3617f4a528b25a69d13aa7","sources":[{"modifiedAt":1793979778715,"name":"CNA: Linux","retrievedAt":1793981740274,"url":"https://www.cve.org/CVERecord?id=CVE-2026-45840"},{"modifiedAt":null,"name":"FIRST EPSS","retrievedAt":1793981759388,"url":"https://api.first.org/data/v1/epss?cve=CVE-2026-45840"}],"ssvc":{"assessedAt":1793979699305,"automatable":"no","exploitation":"none","source":"ADP: CISA-ADP","technicalImpact":"partial"},"status":"published","title":"openvswitch: cap upcall PID array size and pre-size vport replies","updatedAt":1793981759388}