{"id":"CVE-2023-6683","title":"Qemu: vnc: null pointer dereference in qemu_clipboard_request()","summary":"A flaw was found in the QEMU built-in VNC server while processing ClientCutText messages. The qemu_clipboard_request() function can be reached before vnc_server_cut_text_caps() was called and had the chance to initialize the clipboard pe…","severity":"medium","cvss":6.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","cvssSource":"cna","cwe":["CWE-476"],"vendor":"Red Hat","product":"virt-devel:rhel","affected":["virt-devel:rhel (all versions)","virt:rhel (all versions)","qemu-kvm (all versions)","qemu-kvm","qemu-kvm","qemu-kvm-ma","virt:av/qemu-kvm"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2024-07-13T20:19:24.320866Z"},"published":"2024-01-12","updated":"2026-11-05","sourceUpdated":"2026-11-05T11:37:28.638Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2023-6683","references":[{"url":"https://access.redhat.com/errata/RHSA-2024:2135","label":"RHSA-2024:2135"},{"url":"https://access.redhat.com/errata/RHSA-2024:2962","label":"RHSA-2024:2962"},{"url":"https://access.redhat.com/security/cve/CVE-2023-6683"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2254825","label":"RHBZ#2254825"}],"tags":["cve.org"],"epss":0.01261,"epssPercentile":0.69703,"ingestedAt":"2026-11-05T21:36:00.810Z","slug":"CVE-2023-6683","body":"## Overview\n\nA flaw was found in the QEMU built-in VNC server while processing ClientCutText messages. The qemu_clipboard_request() function can be reached before vnc_server_cut_text_caps() was called and had the chance to initialize the clipboard peer, leading to a NULL pointer dereference. This could allow a malicious authenticated VNC client to crash QEMU and trigger a denial of service.\n\n## Affected\n\n- `virt-devel:rhel (all versions)`\n- `virt:rhel (all versions)`\n- `qemu-kvm (all versions)`\n- `qemu-kvm`\n- `qemu-kvm`\n- `qemu-kvm-ma`\n- `virt:av/qemu-kvm`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n### Workarounds\n\nMitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.","depth":"sunlit","depthScore":36,"depthScoreParts":{"impact":35.8,"likelihood":0.3,"exploitation":0,"ransomware":0},"changes":[]}