CVE-2020-9817Public exploit

Root privilege escalation via inherited installer-script ownership

Published Jun 9, 2020 · Updated Aug 4, 2024

Privilege escalation in Apple macOS before 10.15.5 allows local users to execute arbitrary code as root through Installer. Installer extracts package scripts into a world-readable temporary PKInstall sandbox while preserving developer-system UIDs, letting a same-UID process replace scripts before root executes them. Exploitation requires installation or update of a package whose embedded scripts carry an attacker-controlled UID; successful replacement grants full root code execution.

CVSS severity7.8
High
EPSS probability1.06%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Privilege escalation in Apple macOS before 10.15.5 allows local users to execute arbitrary code as root through Installer. Installer extracts package scripts into a world-readable temporary PKInstall sandbox while preserving developer-system UIDs, letting a same-UID process replace scripts before root executes them. Exploitation requires installation or update of a package whose embedded scripts carry an attacker-controlled UID; successful replacement grants full root code execution.

The record

CVE
CVE-2020-9817
Published
Jun 9, 2020
Updated
Aug 4, 2024
Vendor
Apple
Product
macOS
Classifications
CWE-276, T1068
Attack vector
local
Privileges
Unavailable

Timeline

How it unfolded

  1. Jun 9, 2020CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=unspecified <macOS Catalina 10.15.5

What conditions does exploitation require?

Attack vectorlocal
Required privilegesUnavailable in this record.

What is affected?

Apple · macOSversion=unspecified <macOS Catalina 10.15.5

Published CVSS scores

9.3NIST National Vulnerability DatabaseAV:N/AC:M/Au:N/C:C/I:C/A:C
7.8NIST National Vulnerability DatabaseCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-276Incorrect Default Permissions
T1068Exploitation for Privilege Escalation

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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