CVE-2021-3682

HIGH
8.5
CVSS Score
Published: August 5, 2021 at 07:51 PM UTC
Updated: June 17, 2026 at 04:05 AM UTC
3 products affected across 3 vendorsDebian LinuxEnterprise LinuxQEMU

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Severity
HIGH8.5
Exploit prediction
EPSS 3%

Description

A flaw was found in the USB redirector device emulation of QEMU in versions prior to 6.1.0-rc2. It occurs when dropping packets during a bulk transfer from a SPICE client due to the packet queue being full. A malicious SPICE client could use this flaw to make QEMU call free() with faked heap chunk metadata, resulting in a crash of QEMU or potential code execution with the privileges of the QEMU process on the host.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 6.1.06.1.0 rc16.1.0-rc2
Affected range stops below 6.1.0, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (6)

x_refsource_MISCIssue TrackingPatchThird Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=1989651
Mailing Listx_refsource_MLISTThird Party Advisory
https://lists.debian.org/debian-lts-announce/2021/09/msg00000.html
Mailing Listx_refsource_MLISTThird Party Advisory
https://lists.debian.org/debian-lts-announce/2022/09/msg00008.html
Vendor Advisoryx_refsource_GENTOOThird Party Advisory
https://security.gentoo.org/glsa/202208-27
Vendor Advisoryx_refsource_DEBIANThird Party Advisory
https://www.debian.org/security/2021/dsa-4980

CVSS

Attack Vector
NETWORK
Complexity
HIGH
Privileges
LOW
User Interaction
NONE
Scope
CHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-763

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