High severity · published Aug 5, 2021
CVE-2021-3682
A flaw was found in the USB redirector device emulation of QEMU in versions prior to 6.1.0-rc2
8.5
CVSS
2.9%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
Attack vector
Network
Complexity
High
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)2.9% · higher than 87% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DL
Debian Linux · Debian
9.0; 10.0; 11.0 · source: NVD
EL
Enterprise Linux · Redhat
8.0; 8.0 · source: NVD
QE
Qemu · Qemu
before 6.1.0; 6.1.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-3682
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-3682
Issue Tracking
https://bugzilla.redhat.com/show_bug.cgi?id=1989651
Third Party Advisory
https://lists.debian.org/debian-lts-announce/2021/09/msg00000.html
Mailing List
https://lists.debian.org/debian-lts-announce/2022/09/msg00008.html
Third Party Advisory
https://security.gentoo.org/glsa/202208-27
Third Party Advisory
https://security.netapp.com/advisory/ntap-20210902-0006/
Third Party Advisory
https://www.debian.org/security/2021/dsa-4980
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