How severe is CVE-2021-3392?

CVE-2021-3392 has a CVSS 3.x base score of 3.2, rated low severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.

Is CVE-2021-3392 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (36th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-3392?

CVE-2021-3392 primarily affects Qemu. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-3392?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-3392 published?

CVE-2021-3392 was published on 2021-03-23 and last updated on 2026-06-17.

CVE-2021-3392

CVE-2021-3392 is a low-severity vulnerability in Qemu with a CVSS 3.x base score of 3.2. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-416.

Key facts

Severity: Low (CVSS 3.x base score 3.2)
CVSS v2: 2.1
EPSS exploit prediction: 0% (36th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-416
Affected product: Qemu
Published: 2021-03-23
Last modified: 2026-06-17

Description

A use-after-free flaw was found in the MegaRAID emulator of QEMU. This issue occurs while processing SCSI I/O requests in the case of an error mptsas_free_request() that does not dequeue the request object 'req' from a pending requests queue. This flaw allows a privileged guest user to crash the QEMU process on the host, resulting in a denial of service. Versions between 2.10.0 and 5.2.0 are potentially affected.

Frequently asked questions

What is CVE-2021-3392?: A use-after-free flaw was found in the MegaRAID emulator of QEMU. This issue occurs while processing SCSI I/O requests in the case of an error mptsas_free_request() that does not dequeue the request object 'req' from a pending requests queue. This flaw allows a privileged guest user to crash the QEMU process on the host, resulting in a denial of service. Versions between 2.10.0 and 5.2.0 are potentially affected.
How severe is CVE-2021-3392?: CVE-2021-3392 has a CVSS 3.x base score of 3.2, rated low severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.
Is CVE-2021-3392 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (36th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-3392?: CVE-2021-3392 primarily affects Qemu. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-3392?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-3392 published?: CVE-2021-3392 was published on 2021-03-23 and last updated on 2026-06-17.

References

Affected products (4)

cpe:2.3:a:qemu:qemu:*:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*

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