{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-99122","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-09-25T10:25:14.393Z","datePublished":"2026-10-28T10:34:37.859Z","dateUpdated":"2026-10-31T12:43:23.512Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-10-31T12:43:23.512Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nvsock/vmci: validate packet source for connected sockets\n\nvmci_transport_recv_stream_cb() looks up sockets first by the full source\nand destination tuple, then by destination only in the bound table. The\nfallback can select a non-listening socket without checking whether the\npacket came from its stored peer.\n\nThis was reproduced with two VMCI contexts. A RST from the context not\nstored in a TCP_SYN_SENT socket reset that socket after it was selected by\nthe destination-only lookup.\n\nVMCI can process notification packets in bottom-half context when the\nsocket is not owned by user context, or defer packets to a workqueue. Use\nvsock_check_source() after taking the socket lock in the bottom-half path,\nand recheck after lock_sock() in the workqueue path. Listening sockets\ncontinue to accept packets from any source.\n\nReply with a RST addressed from the received packet before dropping a\nsource that fails validation. This preserves the existing reset behavior\nfor bound non-listening and concurrently closed sockets without directing\nthe reset to a connected socket's stored peer."}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:H","baseScore":7.3,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - A local VMCI endpoint supplies the forged control datagram through IOCTL_VMCI_DATAGRAM_SEND, reaching vmci_datagram_dispatch() and the patched vmci_transport_recv_stream_cb(); vsock is therefore Local rather than a routable network vector.\nAC:L - vsock_diag_dump() exposes socket CIDs, ports, and state without an authorization check, after which a chosen RST deterministically misses vsock_find_connected_socket() and reaches the victim through vsock_find_bound_socket(); no race or uncontrolled condition is required.\nPR:L - vmci_host_open(), IOCTL_VMCI_INIT_CONTEXT, and IOCTL_VMCI_DATAGRAM_SEND contain no capability check, allowing a low-privilege VMX/local process with ordinary VMCI-device access to create an unrestricted context and submit the packet.\nUI:N - After the victim process has an ordinary bound connecting or established socket, the attacker's datagram alone drives vmci_transport_recv_pkt_work() and the reset handler; no victim user action is required.\nS:C - A packet owned by an attacker-controlled guest/VMX VMCI context is applied to a host-context socket by vmci_transport_recv_connecting_client() or vmci_transport_recv_connected(), crossing the VMCI virtualization or VMM-sandbox boundary.\nC:L - On an established socket, a forged WAITING_READ reaches vmci_transport_handle_waiting_read(), which conditionally returns WROTE to the foreign source based on vmci_qpair_produce_buf_ready(); this exposes limited queue-occupancy and traffic-state information, not payload bytes.\nI:N - The demonstrated RST and forged notification paths do not write application payloads, alter the intended VMCI queue pair, or corrupt memory; their changes to sk_state, peer_shutdown, and notification flags implement connection disruption rather than data modification.\nA:H - vmci_transport_recv_connecting_client() sets TCP_CLOSE and ECONNRESET, while vmci_transport_recv_connected() sets SOCK_DONE, SHUTDOWN_MASK, and TCP_CLOSING. Because tuples can be re-enumerated and RST injection repeated, the attacker can continuously terminate targeted VMCI client connections and fully deny their service."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/vmw_vsock/vmci_transport.c"],"versions":[{"version":"d021c344051af91f42c5ba9fdedc176740cbd238","lessThan":"c027f8b429dbb2157fc1b503df196e272d947c89","status":"affected","versionType":"git"},{"version":"d021c344051af91f42c5ba9fdedc176740cbd238","lessThan":"90c423b62ec9be08177f74b07a47937ca8d2035b","status":"affected","versionType":"git"},{"version":"d021c344051af91f42c5ba9fdedc176740cbd238","lessThan":"ad9a7da3fa39c2d616ec0dd3cf6e30531d032fe7","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/vmw_vsock/vmci_transport.c"],"versions":[{"version":"3.9","status":"affected"},{"version":"0","lessThan":"3.9","status":"unaffected","versionType":"semver"},{"version":"6.18.59","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.2.13","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":"3.9","versionEndExcluding":"6.18.59"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.9","versionEndExcluding":"7.2.13"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.9","versionEndExcluding":"7.3"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/c027f8b429dbb2157fc1b503df196e272d947c89"},{"url":"https://git.kernel.org/stable/c/90c423b62ec9be08177f74b07a47937ca8d2035b"},{"url":"https://git.kernel.org/stable/c/ad9a7da3fa39c2d616ec0dd3cf6e30531d032fe7"}],"title":"vsock/vmci: validate packet source for connected sockets","x_generator":{"engine":"bippy-1.2.0"}}}}