How severe is CVE-2020-17391?

CVE-2020-17391 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2020-17391 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-17391?

CVE-2020-17391 affects Parallels Parallels Desktop. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-17391?

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

When was CVE-2020-17391 published?

CVE-2020-17391 was published on 2020-08-25 and last updated on 2026-06-17.

CVE-2020-17391

CVE-2020-17391 is a medium-severity vulnerability in Parallels Parallels Desktop with a CVSS 3.x base score of 6.5. 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-749.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 2.1
EPSS exploit prediction: 1% (41st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-749
Affected product: Parallels Parallels Desktop
Published: 2020-08-25
Last modified: 2026-06-17

Description

This vulnerability allows local attackers to disclose information on affected installations of Parallels Desktop 15.1.3-47255. An attacker must first obtain the ability to execute low-privileged code on the target system in order to exploit this vulnerability. The specific flaw exists within the handler for HOST_IOCTL_INIT_HYPERVISOR in the prl_hypervisor kext. The issue results from the exposure of dangerous method or function to the unprivileged user. An attacker can leverage this in conjunction with other vulnerabilities to execute arbitrary code in the context of the kernel. Was ZDI-CAN-10518.

Frequently asked questions

What is CVE-2020-17391?: This vulnerability allows local attackers to disclose information on affected installations of Parallels Desktop 15.1.3-47255. An attacker must first obtain the ability to execute low-privileged code on the target system in order to exploit this vulnerability. The specific flaw exists within the handler for HOST_IOCTL_INIT_HYPERVISOR in the prl_hypervisor kext. The issue results from the exposure of dangerous method or function to the unprivileged user. An attacker can leverage this in conjunction with other vulnerabilities to execute arbitrary code in the context of the kernel. Was ZDI-CAN-10518.
How severe is CVE-2020-17391?: CVE-2020-17391 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2020-17391 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-17391?: CVE-2020-17391 affects Parallels Parallels Desktop. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-17391?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-17391 published?: CVE-2020-17391 was published on 2020-08-25 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:parallels:parallels_desktop:*:*:*:*:*:macos:*:*

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