The PHPOffice library suite allows users to work with spreadsheets, text documents, and presentations in Microsoft Office and OpenDocument formats.
Alexander Zhurnakov, an expert from PT SWARM, helped to fix a vulnerability in the open-source Math library used for processing mathematical formulas. He also helped secure the related PHPWord library, designed for reading and generating text documents in PHP. Before the issue was resolved, the vulnerability could have allowed attackers to access local files or execute requests on behalf of the server. The developer of the open source project was notified of the issue in line with the responsible disclosure policy and has already released updates to the libraries.
PHPWord is widely used among developers. As of June 2025, the library was marked as a favorite by 7,400 users on GitHub, with its repository cloned 2,700 times. In comparison, Math is integrated into PHPWord and is rarely used independently, with only 29 users saving it and just four repository clones recorded.
The vulnerability, identified as CVE-2025-48882, was discovered in Math version 0.2.0 and is rated as highly severe, with the CVSS 4.0 score of 8.7. Due to the interconnected nature of the libraries, the weakness also affected PHPWord starting from version 1.2.0-beta.1. If exploited, the vulnerability could have allowed attackers to access configuration files in applications using the affected libraries.
To mitigate the issue, it is crucial to update to Math 0.3.0 as soon as possible. To prevent attackers from exploiting the vulnerability through the related library, a team of community-driven developers updated the Math dependency in PHPWord. As a result, PHPWord 1.4.0 was released with the fix. For organizations unable to download the patch, Positive Technologies experts recommend an alternative solution: if the application allows uploading files in ODF1 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 successfully exploiting this vulnerability would depend on the capabilities of the application using the vulnerable library. For example, if the targeted system were 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 at the product development stage with the help of a statistical code analysis tool such as PT Application Inspector. Dynamic code analyzers, such as PT BlackBox, are also highly effective. Web application firewalls like PT Application Firewall (also available in the cloud version: PT Cloud Application Firewall) are equally efficient at blocking exploitation attempts. Malicious files can be identified in the network with tools like PT Sandbox, while exploitation attempts can be detected using network traffic analysis solutions, such as PT Network Attack Discovery or PT NGFW.
- OpenDocument Format (ODF) is an open format for storing and sharing files, including text documents, spreadsheets, and presentations. It uses ZIP-compressed XML files.