A significant security flaw in the open-source Math library, a component of the widely used PHPOffice suite, has been successfully patched with the assistance of Alexander Zhurnakov, an expert from Positive Technologies’ PT SWARM team. The PHPOffice library suite enables users to work with various Microsoft Office and OpenDocument formats, including spreadsheets, text documents, and presentations.
The vulnerability, identified as CVE-2025-48882, was discovered in Math version 0.2.0 and received a high severity rating with a CVSS 4.0 score of 8.7. Before its resolution, this flaw could have allowed attackers to access local files or execute requests on behalf of the server. Due to the interconnected nature of the libraries, the weakness also impacted the PHPWord library, used for reading and generating text documents in PHP, starting from version 1.2.0-beta.1. If exploited, the vulnerability could have allowed unauthorized access to configuration files in applications utilizing the affected libraries.
The developer of the open-source project was promptly notified in accordance with responsible disclosure policies and has since released updates for the libraries. To mitigate the risk, it is crucial to update to Math 0.3.0 as soon as possible. Furthermore, a team of community-driven developers updated the Math dependency in PHPWord, resulting in the release of PHPWord 1.4.0 with the fix.
For organizations unable to immediately download the patch, Positive Technologies experts advise an alternative solution: if an application allows uploading files in ODF format, administrators should configure restrictions to block their use.
Alexander Zhurnakov, Software Researcher at Positive Technologies Penetration Testing Department, explained: “Exploitation of this vulnerability would most likely have been carried out by an authorized user through the web interface of an application using PHPWord or Math. An attacker could upload a malicious OpenDocument text file and, during its processing, gain access to configuration files. Using the information in these files, the attacker could potentially obtain administrative access to the application. The attack would primarily target files containing sensitive information. In some cases, the flaw could also be exploited for server-side request forgery (SSRF), allowing the attacker to send requests to the internal network.”
The potential impact of a successful exploitation would depend on the capabilities of the application using the vulnerable library. For instance, if the targeted system was an isolated service for converting documents to PDF, the attacker would likely be unable to cause significant harm to the organization.
Such vulnerabilities can be detected early in the product development stage using static code analysis tools like PT Application Inspector. Dynamic code analyzers such as PT BlackBox are also highly effective. Web application firewalls like PT Application Firewall (also available as PT Cloud Application Firewall) are efficient at blocking exploitation attempts. Additionally, malicious files can be identified in the network with tools such as PT Sandbox, and exploitation attempts can be detected using network traffic analysis solutions like PT Network Attack Discovery or PT NGFW.
