Critical Apache Tika Vulnerability Exposes Systems to Malicious PDF Attacks
A critical security flaw has been identified in Apache Tika, a widely-used open-source toolkit designed for extracting text and metadata from various document formats, including PDFs, Word files, and images. This vulnerability, tracked as CVE-2025-66516, allows attackers to compromise systems by uploading specially crafted PDF files containing malicious code.
Understanding the Vulnerability
The root of this vulnerability lies in an XML External Entity (XXE) injection flaw within Apache Tika’s core library. Attackers can exploit this by embedding malicious XML Forms Architecture (XFA) data inside PDF documents. When Apache Tika processes such a document, it inadvertently executes the embedded code, potentially leading to unauthorized access, data exfiltration, or further exploitation of the affected system.
Affected Components and Versions
This security issue impacts multiple components of Apache Tika across all operating systems:
– Tika-core: Versions 1.13 through 3.2.1 are vulnerable. This is the primary library where the flaw resides.
– Tika-parsers: Versions 1.13 before 2.0.0 are affected. In these versions, the PDF parsing functionality was included within this module.
– Tika PDF parser module: Versions 2.0.0 through 3.2.1 are vulnerable. This module handles PDF parsing in newer versions.
It’s crucial to note that this vulnerability extends beyond the previously reported CVE-2025-54988 in significant ways:
1. Core Library Involvement: While the initial assumption was that the flaw was confined to the PDF parser module, further analysis revealed that the actual vulnerability resides in the Tika-core library. Therefore, updating only the PDF parser module without addressing the core library leaves systems exposed.
2. Legacy System Exposure: Earlier reports did not account for the fact that in Tika’s 1.x releases, the PDF parser was part of the tika-parsers module. This oversight means that legacy systems using these versions are also vulnerable, even if they were believed to be secure.
Immediate Actions Required
Organizations utilizing Apache Tika should take the following steps to mitigate this critical vulnerability:
1. Upgrade Tika-core: Immediately update to version 3.2.2 or later. This update addresses the vulnerability across all affected components.
2. Assess Legacy Systems: For those using older 1.x versions of Tika, it’s imperative to contact your software vendor to obtain patched releases.
3. Restrict Untrusted PDFs: As a temporary measure, limit the processing of PDF files from untrusted external sources until the necessary patches are applied.
Implications for Organizations
Entities that handle sensitive documents, such as financial records, legal papers, and personal data, are at heightened risk due to this vulnerability. The potential for unauthorized access and data breaches underscores the urgency of addressing this issue promptly.
Conclusion
The discovery of CVE-2025-66516 in Apache Tika serves as a stark reminder of the importance of regular software updates and vigilant security practices. Organizations must prioritize patching this vulnerability to safeguard their systems against potential exploits.
