CVE-2026-93834
📛 CVE Title
Qemu-kvm: 9pfs: use-after-free race in tlcreate/twalk allows vm guest escape
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.
Overview
- State
- PUBLISHED
- Assigner (CNA)
- redhat
- CVSS severity
- HIGH
- CVSS score
- 8.8 / 10
- CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H- Effective score
- 8.8 / 10 HIGH source: CNA overview
- CWE(s)
-
CWE-416 - Reserved
- 2026-09-18
- Published
- 2026-09-25 13:36 UTC
- Last updated
- 2026-09-25 13:50 UTC
- Source
- https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/93xxx/CVE-2026-93834.json
- Linked Threat
- CVE-2026-93834 — Qemu-kvm: 9pfs: use-after-free race in tlcreate/twalk allows vm guest escape
NVD triage scoring NVD CVE 2.0
Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.
- NVD published
- 2026-09-25 14:17:24 UTC
- NVD last modified
- 2026-09-25 14:17:24 UTC
- NVD CVSS v3.1
- 8.8 / 10 HIGH source: secalert@redhat.com
- NVD CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H- Exploitability subscore
- 2.0 / 10
- Impact subscore
- 6.0 / 10
NVD / KEV / EPSS data refreshed 2026-09-26 04:37 UTC. Re-run the 🛰 Backfill from NVD button above to refresh.
Affected products (11)
| Vendor | Product | Versions | Platforms |
|---|---|---|---|
| Red Hat | Red Hat Enterprise Linux 10 | — | — |
| Red Hat | Red Hat Enterprise Linux 6 | — | — |
| Red Hat | Red Hat Enterprise Linux 7 | — | — |
| Red Hat | Red Hat Enterprise Linux 7 | — | — |
| Red Hat | Red Hat Enterprise Linux 8 | — | — |
| Red Hat | Red Hat Enterprise Linux 8 | — | — |
| Red Hat | Red Hat Enterprise Linux 9 | — | — |
| Red Hat | Red Hat Enterprise Linux for NVIDIA 26 | — | — |
| Red Hat | Red Hat OpenShift Container Platform 4 | — | — |
| Red Hat | Red Hat OpenShift Container Platform 4 | — | — |
| Red Hat | Red Hat OpenStack Platform 13 (Queens) | — | — |
Vendor references (3)
References embedded in the original CVE record by the assigning CNA.
- https://access.redhat.com/security/cve/CVE-2026-93834 vdb-entryx_refsource_REDHAT
- RHBZ#2537939 issue-trackingx_refsource_REDHAT
- https://gitlab.com/qemu-project/qemu/-/work_items/4491
Web references (0)
DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.
No web references attached yet.
NVD-tagged references (4)
Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.
- https://access.redhat.com/security/cve/CVE-2026-93834 secalert@redhat.com
- https://bugzilla.redhat.com/show_bug.cgi?id=2537939 secalert@redhat.com
- https://gitlab.com/qemu-project/qemu/-/work_items/4491 secalert@redhat.com
- https://gitlab.com/qemu-project/qemu/-/work_items/4491 134c704f-9b21-4f2e-91b3-4a467353bcc0
AI Forensic Analysis
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Raw JSON
The full cvelistV5 record. Download as CVE-2026-93834.json.
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