CVE-2025-48882 is a high-severity vulnerability classified under CWE-611: Improper Restriction of XML External Entity (XXE) Reference, affecting the PHPOffice Math library versions prior to 0.3.0. PHPOffice Math is a PHP library designed to manipulate various formula file formats, relying on XML parsing via the standard libxml extension. The vulnerability arises because the library loads XML data using libxml with the LIBXML_DTDLOAD flag enabled without implementing additional filtering or validation. This configuration allows an attacker to craft malicious XML input containing external entity references, which the parser will resolve. Exploiting this XXE flaw can lead to disclosure of sensitive files, server-side request forgery (SSRF), denial of service (DoS), or other impacts depending on the XML parser's behavior and server configuration. The vulnerability does not require authentication or user interaction and can be triggered remotely by submitting malicious XML data to any system component that uses the vulnerable PHPOffice Math versions. Version 0.3.0 of the library addresses this issue by presumably disabling unsafe XML entity loading or adding proper filtering mechanisms. The CVSS 4.0 base score of 8.7 reflects the high impact on confidentiality (VC:H), with no required privileges or user interaction, and network attack vector, indicating ease of exploitation and significant risk to affected systems. No known exploits are currently reported in the wild, but the vulnerability's nature and severity warrant prompt attention.

For European organizations, the impact of CVE-2025-48882 can be substantial, especially for those relying on PHPOffice Math in web applications, document processing systems, or any service that parses formula files in XML format. Successful exploitation can lead to unauthorized disclosure of sensitive internal files or data, potentially exposing intellectual property, personal data protected under GDPR, or internal network details. Additionally, attackers could leverage SSRF capabilities to pivot into internal networks, increasing the risk of lateral movement and further compromise. Denial of service attacks could disrupt critical business operations, affecting availability. Given the high CVSS score and the lack of required authentication, the vulnerability poses a significant threat to confidentiality and availability, which are critical for compliance and operational continuity in European enterprises. Organizations in sectors such as finance, healthcare, research, and government, where formula processing and document manipulation are common, may be particularly at risk.

European organizations should immediately audit their use of PHPOffice Math and identify any deployments running versions prior to 0.3.0. The primary mitigation is to upgrade to version 0.3.0 or later, which contains the fix for this XXE vulnerability. If upgrading is not immediately feasible, organizations should implement strict input validation and sanitization to reject XML inputs containing external entity declarations or DTDs. Additionally, configuring the libxml parser to disable DTD loading and external entity resolution (e.g., by omitting LIBXML_DTDLOAD or using LIBXML_NONET flags) can mitigate exploitation risk. Employing Web Application Firewalls (WAFs) with rules to detect and block malicious XML payloads can provide an additional layer of defense. Regular security testing, including static and dynamic analysis of XML processing components, should be conducted to detect similar vulnerabilities. Finally, monitoring logs for unusual XML parsing errors or unexpected outbound requests can help identify exploitation attempts early.