Local privilege escalation via permissive extraction directory
Published Jan 14, 2020 · Updated Aug 5, 2024
Privilege escalation in PyInstaller-built Windows onefile executables before 3.6 allows local users to execute code with elevated rights. The bootloader creates its sys._MEIPATH extraction directory with _wmkdir, which does not restrict permissions under a world-writable TempPath. Exploitation requires an unprivileged user to prepare the directory before a higher-privileged executable starts or restarts.
Summary
What happened
Privilege escalation in PyInstaller-built Windows onefile executables before 3.6 allows local users to execute code with elevated rights. The bootloader creates its sys._MEIPATH extraction directory with _wmkdir, which does not restrict permissions under a world-writable TempPath. Exploitation requires an unprivileged user to prepare the directory before a higher-privileged executable starts or restarts.
The record
- CVE
- CVE-2019-16784
- Published
- Jan 14, 2020
- Updated
- Aug 5, 2024
- Vendor
- PyInstaller
- Product
- PyInstaller
- Classifications
- CWE-250, T1574.005
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Jan 14, 2020CVE publishedPublication date reported by the CVE source.
- Aug 5, 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.
- Affected versionversion=< 3.6
What conditions does exploitation require?
What is affected?
Published CVSS scores
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.
Weakness, pattern, technique
Public exploit references
- PyInstaller CVE-2019-16784 exploit demonstrationfunctional · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo