CVE-2026-15705

CVE Details

Release Date:	2026-09-03
Impact:	Low	What is this?

Description

In QEMU's USB redirection (usbredir) implementation, a use-after-free vulnerability exists in the usbredir_buffered_bulk_packet() function in hw/usb/redirect.c. When processing a multi-fragment buffered bulk packet that is split into max-packet-size chunks, only the final fragment owns the shared parser memory allocation (via free_on_destroy). If bufp_alloc() drops the final fragment due to queue overflow, it frees the backing buffer while earlier fragments already queued still hold interior pointers into it. Subsequent guest bulk-IN transfers then read from freed heap memory. A malicious or compromised USB device (or a crafted usbredir stream) could trigger this condition, potentially leading to information disclosure from heap memory or a QEMU process crash (denial of service). This vulnerability has existed since QEMU v1.4.0-rc0 and is fixed in v11.0.3 and v10.0.12.

See more information about CVE-2026-15705 from MITRE CVE dictionary and NIST NVD

NOTE: The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v3 metrics

Base Score:	6.4
Vector String:	CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:L/I:N/A:H
Version:	3.1
Attack Vector:	Local
Attack Complexity:	High
Privileges Required:	Low
User Interaction:	None
Scope:	Changed
Confidentiality Impact:	Low
Integrity Impact:	None
Availability Impact:	High

Errata information

Platform	Errata	Release Date
Oracle Linux version 9 (qemu-kvm)	ELSA-2026-500245	2026-09-03