{"cve":"CVE-2023-3354","nvd":{"published":"2023-07-11T17:15:13.387","modified":"2026-06-17T06:13:52.787","status":"Modified","description":"A flaw was found in the QEMU built-in VNC server. When a client connects to the VNC server, QEMU checks whether the current number of connections crosses a certain threshold and if so, cleans up the previous connection. If the previous connection happens to be in the handshake phase and fails, QEMU cleans up the connection again, resulting in a NULL pointer dereference issue. This could allow a remote unauthenticated client to cause a denial of service.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":["CWE-476"],"references":["https://access.redhat.com/security/cve/CVE-2023-3354","https://bugzilla.redhat.com/show_bug.cgi?id=2216478","https://lists.debian.org/debian-lts-announce/2024/03/msg00012.html","https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/MURWGXDIF2WTDXV36T6HFJDBL632AO7R/","https://access.redhat.com/security/cve/CVE-2023-3354"],"products":["fedoraproject:fedora","qemu:qemu","redhat:enterprise_linux","redhat:openstack_platform"],"source":"nvd","synced_at":"2026-10-19T21:38:30.124994567+00:00"},"epss":{"cve":"CVE-2023-3354","score":0.01606,"percentile":0.75882,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}