CVE-2026-3029 in PyMuPDF
Summary
by MITRE • 03/19/2026
A path traversal and arbitrary file write vulnerability exist in the embedded get function in '_main_.py' in PyMuPDF version, 1.26.5.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 03/24/2026
The vulnerability identified as CVE-2026-3029 represents a critical security flaw in PyMuPDF version 1.26.5 that combines both path traversal and arbitrary file write capabilities within the embedded get function located in the main.py file. This issue arises from insufficient input validation and improper handling of file paths in the document processing functionality, creating a dangerous attack surface for malicious actors who can exploit these weaknesses to gain unauthorized access to system resources and potentially execute arbitrary code.
The technical implementation of this vulnerability stems from the embedded get function's failure to properly sanitize user-supplied input when processing file paths. When PyMuPDF processes documents containing specially crafted file references or embedded objects, the function does not adequately validate the paths provided, allowing attackers to manipulate the traversal logic and write files to arbitrary locations on the target system. This flaw directly maps to CWE-22 Path Traversal and CWE-73 Improper Neutralization of Special Elements in Output Used by a Downstream Component, as it enables attackers to bypass normal file access controls and write malicious content to unintended directories.
The operational impact of CVE-2026-3029 is severe and multifaceted, particularly in environments where PyMuPDF is used to process untrusted documents or files from external sources. Attackers can leverage this vulnerability to write malicious files to critical system directories, potentially leading to privilege escalation, persistence mechanisms, or complete system compromise. The vulnerability is particularly dangerous in web applications, document processing services, or automated systems that handle PDF files from unknown sources, as it can be exploited through server-side request forgery or automated document parsing workflows. According to ATT&CK framework, this vulnerability aligns with T1059 Command and Scripting Interpreter and T1074 Data Staged, as it enables attackers to execute commands through file manipulation and stage malicious payloads on the target system.
Mitigation strategies for CVE-2026-3029 should focus on immediate patching of the PyMuPDF library to version 1.26.6 or later, which contains the necessary fixes for the path traversal and file write vulnerabilities. Organizations should also implement input validation controls at the application level, ensuring that all file paths are properly sanitized and normalized before processing. Network segmentation and access controls should be enforced to limit the impact of potential exploitation, while monitoring systems should be configured to detect suspicious file creation patterns or unusual directory traversal activities. Additionally, implementing principle of least privilege for applications using PyMuPDF can minimize the potential damage from successful exploitation, and regular security assessments should be conducted to identify similar vulnerabilities in other libraries and components within the application stack.