CVE-2026-6425

CVE Details

Release Date:	2026-08-19
Impact:	Important	What is this?

Description

libvhost-user: fix buffer overflow in virtqueue_read_indirect_desc() virtqueue_read_indirect_desc() copies an indirect descriptor table into a buffer in chunks when the table crosses a memory region boundary. The destination is a struct vring_desc pointer but is advanced by a byte count, so each increment moves the pointer by read_len elements instead of read_len bytes, writing beyond the buffer. Use a char pointer for the destination so that the arithmetic advances correctly. While at it, change the source from a struct vring_desc pointer to a void pointer: when the table is split across regions, vu_gpa_to_va() can return a pointer into the middle of a descriptor, so casting it to a struct vring_desc pointer is wrong. The pointer is only used as a memcpy() source, so a void pointer is fine.

See more information about CVE-2026-6425 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:	7.8
Vector String:	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Version:	3.1
Attack Vector:	Local
Attack Complexity:	Low
Privileges Required:	Low
User Interaction:	None
Scope:	Unchanged
Confidentiality Impact:	High
Integrity Impact:	High
Availability Impact:	High

Errata information

Platform	Errata	Release Date
Oracle Linux version 9 (qemu-kvm)	ELSA-2026-500220	2026-08-19