{"id":"CVE-2026-93834","aliases":[],"cve":{"records":[{"id":"CVE-2026-93834","source":"redhat","state":"PUBLISHED","reasons":[],"replacements":[],"disputed":false,"unsupportedWhenAssigned":false,"reserved":"2026-09-18T18:12:23.908Z","published":"2026-09-25T13:36:17.597Z","modified":"2026-11-05T00:12:18.099Z"}],"publishers":[{"name":"redhat","role":"CNA","organizationId":"53f830b8-0a3f-465b-8143-3b8a9948e749","modified":"2026-11-05T00:12:18.099Z"},{"name":"CISA-ADP","role":"ADP","organizationId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","modified":"2026-09-25T13:50:26.440Z"}],"references":[{"url":"https://access.redhat.com/security/cve/CVE-2026-93834","tags":["vdb-entry","x_refsource_REDHAT"],"source":"redhat"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2537939","tags":["issue-tracking","x_refsource_REDHAT"],"source":"redhat"},{"url":"https://gitlab.com/qemu-project/qemu/-/work_items/4491","tags":[],"source":"redhat"},{"url":"https://gitlab.com/qemu-project/qemu/-/work_items/4491","tags":["exploit"],"source":"CISA-ADP"}],"weaknesses":[{"id":"CWE-416","description":"Use After Free","source":"redhat"}],"applicability":[],"prioritization":[{"source":"CISA-ADP","type":"SSVC","role":"CISA Coordinator","timestamp":"2026-09-25T13:49:32.754375Z","decisions":[{"name":"Exploitation","value":"poc"},{"name":"Automatable","value":"no"},{"name":"Technical Impact","value":"total"}]}]},"title":"Qemu-kvm: 9pfs: use-after-free race in tlcreate/twalk allows vm guest escape","titleSource":"redhat","descriptionSource":"redhat","description":"A use-after-free vulnerability was found in QEMU's 9pfs subsystem. A race condition between the main thread and a worker thread when processing concurrent Tlcreate and Twalk requests allows a malicious guest user to craft a fid path containing stale heap data, bypassing directory traversal restrictions and escaping the shared directory boundary. This can lead to arbitrary host file read/write and code execution (VM escape) as the QEMU process user.","score":8.8,"severity":"high","published":"2026-09-25T13:36:17.597Z","modified":"2026-11-05T00:12:18.099Z","withdrawn":false,"knownExploited":false,"affected":[],"products":[{"vendor":"Red Hat","name":"Red Hat Enterprise Linux 10","platforms":[],"versions":[],"defaultStatus":"affected","cpes":["cpe:/a:redhat:enterprise_linux:10"],"source":"redhat","url":"https://www.cve.org/CVERecord?id=CVE-2026-93834"},{"vendor":"Red Hat","name":"Red Hat Enterprise Linux 6","platforms":[],"versions":[],"defaultStatus":"unaffected","cpes":["cpe:/o:redhat:rhel_els:6"],"source":"redhat","url":"https://www.cve.org/CVERecord?id=CVE-2026-93834"},{"vendor":"Red Hat","name":"Red Hat Enterprise Linux 7","platforms":[],"versions":[],"defaultStatus":"unaffected","cpes":["cpe:/o:redhat:rhel_els:7"],"source":"redhat","url":"https://www.cve.org/CVERecord?id=CVE-2026-93834"},{"vendor":"Red Hat","name":"Red Hat Enterprise Linux 7","platforms":[],"versions":[],"defaultStatus":"unaffected","cpes":["cpe:/o:redhat:rhel_els:7"],"source":"redhat","url":"https://www.cve.org/CVERecord?id=CVE-2026-93834"},{"vendor":"Red Hat","name":"Red Hat Enterprise Linux 8","platforms":[],"versions":[],"defaultStatus":"affected","cpes":["cpe:/a:redhat:enterprise_linux:8"],"source":"redhat","url":"https://www.cve.org/CVERecord?id=CVE-2026-93834"},{"vendor":"Red Hat","name":"Red Hat Enterprise Linux 8","platforms":[],"versions":[],"defaultStatus":"affected","cpes":["cpe:/a:redhat:enterprise_linux:8"],"source":"redhat","url":"https://www.cve.org/CVERecord?id=CVE-2026-93834"},{"vendor":"Red Hat","name":"Red Hat Enterprise Linux 9","platforms":[],"versions":[],"defaultStatus":"affected","cpes":["cpe:/a:redhat:enterprise_linux:9"],"source":"redhat","url":"https://www.cve.org/CVERecord?id=CVE-2026-93834"},{"vendor":"Red Hat","name":"Red Hat Enterprise Linux for NVIDIA 26","platforms":[],"versions":[],"defaultStatus":"unknown","cpes":["cpe:/a:redhat:enterprise_linux_nvidia:"],"source":"redhat","url":"https://www.cve.org/CVERecord?id=CVE-2026-93834"},{"vendor":"Red Hat","name":"Red Hat OpenShift Container Platform 4","platforms":[],"versions":[],"defaultStatus":"affected","cpes":["cpe:/a:redhat:openshift:4"],"source":"redhat","url":"https://www.cve.org/CVERecord?id=CVE-2026-93834"},{"vendor":"Red Hat","name":"Red Hat OpenShift Container Platform 4","platforms":[],"versions":[],"defaultStatus":"affected","cpes":["cpe:/a:redhat:openshift:4"],"source":"redhat","url":"https://www.cve.org/CVERecord?id=CVE-2026-93834"},{"vendor":"Red Hat","name":"Red Hat OpenShift Container Platform 5","platforms":[],"versions":[],"defaultStatus":"affected","cpes":["cpe:/a:redhat:openshift:5"],"source":"redhat","url":"https://www.cve.org/CVERecord?id=CVE-2026-93834"},{"vendor":"Red Hat","name":"Red Hat OpenStack Platform 13 (Queens)","platforms":[],"versions":[],"defaultStatus":"unaffected","cpes":["cpe:/a:redhat:openstack:13"],"source":"redhat","url":"https://www.cve.org/CVERecord?id=CVE-2026-93834"}],"remediation":[{"text":"Do not configure 9pfs/VirtFS filesystem sharing (-fsdev, -virtfs) on affected QEMU instances. If host-guest file sharing is required, use virtio-fs (virtiofsd) as an alternative, which does not use the vulnerable 9pfs code path.","source":"redhat","url":"https://www.cve.org/CVERecord?id=CVE-2026-93834"}],"references":["https://access.redhat.com/security/cve/CVE-2026-93834","https://bugzilla.redhat.com/show_bug.cgi?id=2537939","https://gitlab.com/qemu-project/qemu/-/work_items/4491"],"sources":[{"name":"CVE","id":"CVE-2026-93834","modified":"2026-11-05T00:12:18.099Z","url":"https://www.cve.org/CVERecord?id=CVE-2026-93834"}],"assessments":[{"source":"redhat","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","score":8.8}],"sourceAffected":[],"observedAt":"2026-11-05T06:57:13.844Z","kev":{"status":"not-listed","checkedAt":"2026-11-14T23:25:34.978Z"},"coverage":[{"source":"NVD","status":"available","checkedAt":"2026-10-31T11:30:32.938Z","attemptedAt":"2026-10-31T11:30:32.938Z"},{"source":"GHSA","status":"available","checkedAt":"2026-10-31T11:30:32.932Z","attemptedAt":"2026-10-31T11:30:32.932Z"},{"source":"EUVD","status":"available","checkedAt":"2026-10-31T11:30:32.030Z","attemptedAt":"2026-10-31T11:30:32.030Z"},{"source":"EPSS","status":"available","checkedAt":"2026-10-31T11:30:32.932Z","attemptedAt":"2026-10-31T11:30:32.932Z"}],"evidence":[{"source":"ENISA EUVD","id":"EUVD-2026-87092","url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-87092","modified":"Oct 31, 2026, 7:56:30 AM","score":8.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","checkedAt":"2026-10-31T11:30:32.030Z"},{"source":"GitHub Advisory Database","id":"GHSA-86c2-8qp8-q2vh","url":"https://github.com/advisories/GHSA-86c2-8qp8-q2vh","modified":"2026-09-25T15:31:54Z","score":8.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","checkedAt":"2026-10-31T11:30:32.932Z"},{"source":"FIRST EPSS","id":"CVE-2026-93834","url":"https://www.first.org/epss/","probability":0.00405,"percentile":0.34723,"date":"2026-10-30","checkedAt":"2026-10-31T11:30:32.932Z"},{"source":"NVD","id":"CVE-2026-93834","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-93834","modified":"2026-10-31T08:16:49.610","score":8.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","checkedAt":"2026-10-31T11:30:32.938Z"}],"aiSummary":{"text":"A use-after-free vulnerability in QEMU's 9pfs subsystem allows a malicious guest user to escape the shared directory boundary, potentially leading to arbitrary host file read/write. The vulnerability is due to a race condition between the main thread and a worker thread when processing concurrent Tlcreate and Twalk requests. Affected products include Red Hat Enterprise Linux 8, 9, and 10.","model":"@cf/meta/llama-3.3-70b-instruct-fp8-fast","generatedAt":"2026-11-05T07:01:04.411Z","sources":[{"name":"CVE","url":"https://www.cve.org/CVERecord?id=CVE-2026-93834"}]}}