{"id":"CVE-2026-53181","summary":"vsock/vmci: fix sk_ack_backlog leak on failed handshake","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nvsock/vmci: fix sk_ack_backlog leak on failed handshake\n\nWhen vmci_transport_recv_connecting_server() returns an error,\nvmci_transport_recv_listen() calls vsock_remove_pending() but never\ncalls sk_acceptq_removed(). This leaves sk_ack_backlog incremented\npermanently.\n\nRepeated handshake failures (malformed packets, queue pair alloc\nfailure, event subscribe failure) cause sk_ack_backlog to climb\ntoward sk_max_ack_backlog. Once it reaches the limit the listener\npermanently refuses all new connections with -ECONNREFUSED, a\nsilent denial of service requiring a process restart to recover.\n\nThe two existing sk_acceptq_removed() calls in af_vsock.c do not\ncover this path: line 764 checks vsock_is_pending() which returns\nfalse after vsock_remove_pending(), and line 1889 is only reached\non successful accept().\n\nFix by balancing sk_acceptq_added() with sk_acceptq_removed() on\nthe error path.","modified":"2026-07-08T08:07:23.603248580Z","published":"2026-06-25T08:38:55.994Z","related":["CGA-jx69-6fxg-xf74"],"database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53181.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/22c587aa3ab1ab5264daff3ec32136fd30436c13"},{"type":"WEB","url":"https://git.kernel.org/stable/c/9698582a4dd9c4a05889d7db96d4c0edc9e69cac"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ba9ad6015937a5e46ba1a31370e3efdec8abbdcc"},{"type":"WEB","url":"https://git.kernel.org/stable/c/bcb275626055df7f8f947f1a349754b4004d9a15"},{"type":"WEB","url":"https://git.kernel.org/stable/c/c05fa14db43ebef3bd862ca9d073981c0358b3f0"},{"type":"WEB","url":"https://git.kernel.org/stable/c/cf7090e255d74c4b61c51f8ede9fcacdd8393b5b"},{"type":"WEB","url":"https://git.kernel.org/stable/c/dfd853197615d322d3a88dbcab91fc0fd2096219"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ea0b03d52881c12a8c634ea0d6cbfa61cefdb488"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53181.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-53181"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"d021c344051af91f42c5ba9fdedc176740cbd238"},{"fixed":"22c587aa3ab1ab5264daff3ec32136fd30436c13"},{"fixed":"cf7090e255d74c4b61c51f8ede9fcacdd8393b5b"},{"fixed":"ea0b03d52881c12a8c634ea0d6cbfa61cefdb488"},{"fixed":"dfd853197615d322d3a88dbcab91fc0fd2096219"},{"fixed":"bcb275626055df7f8f947f1a349754b4004d9a15"},{"fixed":"ba9ad6015937a5e46ba1a31370e3efdec8abbdcc"},{"fixed":"9698582a4dd9c4a05889d7db96d4c0edc9e69cac"},{"fixed":"c05fa14db43ebef3bd862ca9d073981c0358b3f0"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-53181.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.9.0"},{"fixed":"5.10.259"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.210"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.176"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.143"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.94"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.36"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.0.13"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-53181.json"}}],"schema_version":"1.7.5"}