CVE-2021-3682

mediumpriority · track · 35EPSS 0.029 · 87 %ileDEEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

2.88% (87th) EPSS

CVSS 6 · medium

Is it mine?

22 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-27

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.

cvss

Technical severity, 0–10. One row per scoring source.

8.5

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6–8.5

v2.06mediumAV:N/AC:M/Au:S/C:P/I:P/A:Pprimary · NVD / NIST USexploitability 6.8 · impact 6.4

v3.18.5highCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 1.8 · impact 6

v3.18.5highAV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU

v3.17.8highCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-763USCWE-763US

affected products (22)

Products and version ranges known to be affected.

Debian Linuxall versionscert_bundDEcpe:/o:debian:debian_linux:-
Gentoo Linuxall versionscert_bundDEcpe:/o:gentoo:linux:-
Open Source QEMU <6.1.0-rc2all versionscert_bundDE
Oracle Linuxall versionscert_bundDEcpe:/o:oracle:linux:-
Red Hat Enterprise Linuxall versionscert_bundDEcpe:/o:redhat:enterprise_linux:-
Red Hat Virtualizationall versionscert_bundDEcpe:/a:redhat:virtualization:-
SUSE Linuxall versionscert_bundDEcpe:/o:suse:suse_linux:-
Ubuntu Linuxall versionscert_bundDEcpe:/o:canonical:ubuntu_linux:-
Open Source QEMU< 6.1.0-rc2cert_bundDE
n/a qemu≤ qemu 6.1.0-rc2enisa_euvdEU
Fabrice Bellard QEMU≤ 6.1.0-rc2fstec_bduRU
АО «Концерн ВНИИНС» ОС ОН «Стрелец»≤ 16.01.2023fstec_bduRU
АО «НППКТ» ОСОН ОСнова Оnyx≤ 2.5fstec_bduRU
ООО «РусБИТех-Астра» Astra Linux Special Edition≤ 1.7fstec_bduRU
Сообщество свободного программного обеспечения Debian GNU/Linux≤ 11fstec_bduRU
Сообщество свободного программного обеспечения Debian GNU/Linux≤ 10fstec_bduRU
debian debian linux= 10.0nvdUScpe:2.3:o:debian:debian_linux:*:*:*:*:*:*:*:*
debian debian linux= 11.0nvdUScpe:2.3:o:debian:debian_linux:*:*:*:*:*:*:*:*
debian debian linux= 9.0nvdUScpe:2.3:o:debian:debian_linux:*:*:*:*:*:*:*:*
qemu qemu< 6.1.0nvdUScpe:2.3:a:qemu:qemu:*:*:*:*:*:*:*:*

showing 20 of 22

advisories (2)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2022-1118QEMU: Schwachstelle ermöglicht Ausführen von beliebigem Programmcode mit den Rechten des DienstesDeutsch2021-08-05csaf · cert_bundDE
Ein entfernter, authentisierter Angreifer kann eine Schwachstelle in QEMU ausnutzen, um beliebigen Programmcode mit den Rechten des Dienstes auszuführen und einen Denial of Service Zustand herzustellen.
WID-SEC-W-2022-1728Red Enterprise Linux Advanced Virtualization: Mehrere SchwachstellenDeutsch2021-09-30csaf · cert_bundDE
Ein entfernter oder lokaler, authentisierter Angreifer kann mehrere Schwachstellen in Red Enterprise Linux Advanced Virtualization ausnutzen, um einen Denial of Service zu verursachen, Sicherheitsvorkehrungen zu umgehen, beliebigen Code auszuführen und Informationen offenzulegen.

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu cert_bund nvd NVD CVE.org MITRE

published 2021-08-05modified 2026-06-17

references (33)

External citations — patches, advisories, analysis.

scry

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