HOMEVULNERABILITIESCVE-2021-3930
MEDIUM

CVE-2021-3930

CWE-193Published: February 18, 2022· Updated: Jun 17, 2026

6.5
CVSS v3.1

Official Description

An off-by-one error was found in the SCSI device emulation in QEMU. It could occur while processing MODE SELECT commands in mode_sense_page() if the 'page' argument was set to MODE_PAGE_ALLS (0x3f). A malicious guest could use this flaw to potentially crash QEMU, resulting in a denial of service condition.

NVD Source

Technical Analysis

CVE-2021-3930 requires local access, meaning attackers must already have a foothold on the target system.

Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.

A successful exploit results in availability disruption (denial of service), with a CVSS base score of 6.5.

The vulnerability has a "Changed" scope, meaning successful exploitation can impact components beyond the vulnerable component itself — such as the host operating system or adjacent services.

CVSS v3.1 Vector Breakdown

Exploitability
Attack VectorLocal
Attack ComplexityLow
Privileges Req.Low
User InteractionNone
ScopeChanged
Impact
ConfidentialityNone
IntegrityNone
AvailabilityHigh
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H

Affected Vendors & Products

Debian1 product(s)
debian linux
qemu1 product(s)
qemu
Red Hat8 product(s)
codeready linux buildercodeready linux builder for ibm z systemscodeready linux builder for power little endianopenstackenterprise linuxenterprise linux advanced virtualization eusenterprise linux for ibm z systemsenterprise linux for power little endian
Source: NVD CPE · 12 total CPE entries

Exploit & PoC Resources

NO KNOWN EXPLOITNo public exploit confirmed at this time
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Official Patches & Advisories

All References (10)

Quick Facts

CVE IDCVE-2021-3930
CVSS Score6.5 / 10
SeverityMEDIUM
WeaknessCWE-193
CISA KEVNo
Affected3 vendor(s)
PublishedFeb 18, 2022

Related CVEs (CWE-193)

Recommended Actions

  • Apply vendor patches immediately
  • Monitor CVE-2021-3930 in threat intel feeds
  • Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWATCH.COM. CVE data is provided under the NVD usage policy.