CVE-2025-54988 is a critical XML External Entity (XXE) vulnerability affecting the Apache Tika PDF parser module, specifically versions from 1.13 through 3.2.1. Apache Tika is a widely used content analysis toolkit that extracts metadata and text from various file formats, including PDFs. The vulnerability arises from improper restriction of XML External Entity references (CWE-611) in the tika-parser-pdf-module when processing XFA (XML Forms Architecture) files embedded inside PDFs. An attacker can craft a malicious PDF containing a specially designed XFA form that triggers the XXE injection during parsing. This allows the attacker to read sensitive files on the host system or induce the parser to make unauthorized requests to internal network resources or external third-party servers. The vulnerability is particularly severe because the tika-parser-pdf-module is a dependency in multiple Apache Tika packages such as tika-parsers-standard-modules, tika-parsers-standard-package, tika-app, tika-grpc, and tika-server-standard, thus broadening the attack surface. Exploitation does not require user interaction beyond processing the malicious PDF file, and no authentication is needed if the vulnerable service is exposed. Although no known exploits are currently reported in the wild, the risk is significant due to the ability to exfiltrate sensitive data or pivot attacks within internal networks. The issue is resolved in Apache Tika version 3.2.2, which includes proper mitigation against XXE attacks in the PDF parser module.

For European organizations, this vulnerability poses a substantial risk, especially for those relying on Apache Tika for document processing, content indexing, or data extraction workflows. Sensitive information such as internal documents, personally identifiable information (PII), or intellectual property could be exposed if malicious PDFs are processed by vulnerable systems. Additionally, the ability to make unauthorized requests to internal resources could facilitate lateral movement within corporate networks or enable attackers to bypass perimeter defenses. Organizations in sectors with strict data protection regulations, such as finance, healthcare, and government, face heightened compliance risks and potential reputational damage if breaches occur. The vulnerability could also be leveraged in supply chain attacks if third-party services or applications incorporate vulnerable Tika components. Given the widespread use of Apache Tika in enterprise content management systems and data processing pipelines, the potential impact on confidentiality and integrity is high, while availability impact is moderate but possible if exploitation triggers denial-of-service conditions.

European organizations should immediately audit their software stacks to identify usage of Apache Tika versions 1.13 through 3.2.1, particularly focusing on components that include the tika-parser-pdf-module or its dependent packages. The primary mitigation is to upgrade all affected Apache Tika components to version 3.2.2 or later, which contains the fix for this XXE vulnerability. Where immediate upgrades are not feasible, organizations should implement strict input validation and sandboxing for document processing services to isolate the parsing environment and prevent unauthorized network access. Network segmentation and egress filtering can limit the ability of exploited systems to reach internal or external resources. Monitoring and logging of document processing activities should be enhanced to detect anomalous behavior indicative of exploitation attempts. Additionally, organizations should educate users and administrators about the risks of processing untrusted PDF files, especially those containing embedded XFA forms. Finally, applying runtime application self-protection (RASP) or web application firewall (WAF) rules that detect and block XXE payload patterns can provide an additional layer of defense.