Skip to main content

Pyinstaller CVE-2023-49797

HIGH
Creation of Temporary File in Directory with Insecure Permissions (CWE-379)
2023-12-09 security-advisories@github.com
7.8
CVSS 3.1 · NVD
View

Vulnerability Assessment

Weakness
CWE
OWASP Top 10:2025
A01:2025 - Broken Access Control
ASVS 5.0
V5 - File Handling Temp file permissions
Impact

CVSS score of 7.8 (HIGH). Attack characteristics: local attack vector, low complexity, low privileges required, no user interaction not required.

Exploit ScenarioDerived

Successful exploitation could compromise the high-severity affected system.

This Week Schedule remediation this week. Why: HIGH severity (CVSS 7.0-8.9).
Patch available 0.3% exploitation probability (EPSS)

Get an e-mail when this CVE is exploited, patched or re-scored. Free account.

Alert me

AnalysisAI

PyInstaller bundles a Python application and all its dependencies into a single package. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity.

RemediationAI

A vendor patch is available. Apply the latest security update as soon as possible. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.

Affected Packages

pypi pyinstaller fix: 5.13.1

Source: OSV (Open Source Vulnerabilities)

Affects your stack

Affects 1 package in pypi

Checking this CVE against your own stacks and servers is part of the Basic plan and up.

Technical ContextAI · show details

This vulnerability is classified under CWE-379. PyInstaller bundles a Python application and all its dependencies into a single package. A PyInstaller built application, elevated as a privileged process, may be tricked by an unprivileged attacker into deleting files the unprivileged user does not otherwise have access to. A user is affected if all the following are satisfied: 1. The user runs an application containing either matplotlib or win32com. 2. The application is ran as administrator (or at least a user with higher privileges than the attacker). 3. The user's temporary directory is not locked to that specific user (most likely due to TMP/TEMP environment variables pointing to an unprotected, arbitrary, non default location). Either: A. The attacker is able to very carefully time the replacement of a temporary file with a symlink. This switch must occur exactly between shutil.rmtree()'s builtin symlink check and the deletion itself B: The application was built with Python 3.7.x or earlier which has no protection against Directory Junctions links. The vulnerability has been addressed in PR #7827 which corresponds to pyinstaller >= 5.13.1. Users are advised to upgrade. There are no known workarounds for this vulnerability. Affected products include: Pyinstaller.

Know when Pyinstaller gets its next vulnerability

  • Watch products and get an email when something new is published
  • Check this CVE against your own stack and servers
  • Exploit and PoC references, threat intelligence from 22 sources

No credit card · 7-day full trial

Severity by source

NVD PRIMARY 7.8 HIGH
AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

DescriptionNVD

PyInstaller bundles a Python application and all its dependencies into a single package. A PyInstaller built application, elevated as a privileged process, may be tricked by an unprivileged attacker into deleting files the unprivileged user does not otherwise have access to. A user is affected if all the following are satisfied: 1. The user runs an application containing either matplotlib or win32com. 2. The application is ran as administrator (or at least a user with higher privileges than the attacker). 3. The user's temporary directory is not locked to that specific user (most likely due to TMP/TEMP environment variables pointing to an unprotected, arbitrary, non default location). Either: A. The attacker is able to very carefully time the replacement of a temporary file with a symlink. This switch must occur exactly between shutil.rmtree()'s builtin symlink check and the deletion itself B: The application was built with Python 3.7.x or earlier which has no protection against Directory Junctions links. The vulnerability has been addressed in PR #7827 which corresponds to pyinstaller >= 5.13.1. Users are advised to upgrade. There are no known workarounds for this vulnerability.

Threat Intelligence Overview

EPSS Score
0.3%
Top 76% exploitable
Data Quality
3 sources
Confidence: Low

How this decision was reached

The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.

SignalValue
Severity HIGH
CISA KEV No
Public POC No
EPSS 0.3%
Patch available Yes
Active threat No
Deciding rule
HIGH severity (CVSS 7.0-8.9)
What every action level means
Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.
Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.
This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.
This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.
Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.

SSVC AssessmentENISA

SSVC Decision· derived
Defer
Exploitation· derived
None
System Exposure· derived
Small
Automatable· derived
No
Human Impact· derived
Medium

Priority Score

39
Low Medium High Critical
KEV: 0
EPSS: 0
CVSS: +39
PoC: 0
Weaponized: 0
Threat intel: 0
Gov advisory: 0

Attack Technique

Information disclosure occurs when an application unintentionally exposes sensitive data that aids attackers in reconnaissance or directly compromises security.

Affected Products (CPE)NVD

cpe:2.3:a:pyinstaller:pyinstaller:*:*:*:*:*:*:*:*

This site uses cookies essential for authentication and security. No tracking or analytics cookies are used. Privacy Policy