How severe is CVE-2020-9856?

CVE-2020-9856 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.

Is CVE-2020-9856 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (69th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-9856?

CVE-2020-9856 primarily affects Apple Mac Os X. In total, 25 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-9856?

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

When was CVE-2020-9856 published?

CVE-2020-9856 was published on 2020-06-09 and last updated on 2026-06-17.

CVE-2020-9856

CVE-2020-9856 is a medium-severity vulnerability in Apple Mac Os X with a CVSS 3.x base score of 5.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 4.6
EPSS exploit prediction: 1% (69th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Apple Mac Os X
Published: 2020-06-09
Last modified: 2026-06-17

Description

This issue was addressed with improved checks. This issue is fixed in macOS Catalina 10.15.5. An application may be able to gain elevated privileges.

Frequently asked questions

What is CVE-2020-9856?: This issue was addressed with improved checks. This issue is fixed in macOS Catalina 10.15.5. An application may be able to gain elevated privileges.
How severe is CVE-2020-9856?: CVE-2020-9856 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.
Is CVE-2020-9856 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (69th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-9856?: CVE-2020-9856 primarily affects Apple Mac Os X. In total, 25 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-9856?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-9856 published?: CVE-2020-9856 was published on 2020-06-09 and last updated on 2026-06-17.

References

https://support.apple.com/HT211170

Affected products (25)

cpe:2.3:o:apple:mac_os_x:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.13.6:*:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.13.6:-:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.13.6:security_update_2018-002:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.13.6:security_update_2018-003:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.13.6:security_update_2019-001:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.13.6:security_update_2019-002:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.13.6:security_update_2019-003:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.13.6:security_update_2019-004:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.13.6:security_update_2019-005:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.13.6:security_update_2019-006:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.13.6:security_update_2019-007:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.13.6:security_update_2020-001:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.13.6:security_update_2020-002:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.14.6:*:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.14.6:-:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2019-001:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2019-002:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2019-004:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2019-005:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2019-006:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2019-007:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2020-001:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2020-002:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2020-003:*:*:*:*:*:*

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