How severe is CVE-2020-35506?

CVE-2020-35506 has a CVSS 3.x base score of 6.7, rated medium severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2020-35506 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (29th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-35506?

CVE-2020-35506 affects Qemu. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-35506?

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

When was CVE-2020-35506 published?

CVE-2020-35506 was published on 2021-05-28 and last updated on 2026-06-17.

CVE-2020-35506

CVE-2020-35506 is a medium-severity vulnerability in Qemu with a CVSS 3.x base score of 6.7. 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: Medium (CVSS 3.x base score 6.7)
CVSS v2: 4.6
EPSS exploit prediction: 0% (29th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-416
Affected product: Qemu
Published: 2021-05-28
Last modified: 2026-06-17

Description

A use-after-free vulnerability was found in the am53c974 SCSI host bus adapter emulation of QEMU in versions before 6.0.0 during the handling of the 'Information Transfer' command (CMD_TI). This flaw allows a privileged guest user to crash the QEMU process on the host, resulting in a denial of service or potential code execution with the privileges of the QEMU process.

Frequently asked questions

What is CVE-2020-35506?: A use-after-free vulnerability was found in the am53c974 SCSI host bus adapter emulation of QEMU in versions before 6.0.0 during the handling of the 'Information Transfer' command (CMD_TI). This flaw allows a privileged guest user to crash the QEMU process on the host, resulting in a denial of service or potential code execution with the privileges of the QEMU process.
How severe is CVE-2020-35506?: CVE-2020-35506 has a CVSS 3.x base score of 6.7, rated medium severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-35506 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (29th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-35506?: CVE-2020-35506 affects Qemu. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-35506?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-35506 published?: CVE-2020-35506 was published on 2021-05-28 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:qemu:qemu:*:*:*:*:*:*:*:*

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