CVE-2025-50420 is a vulnerability identified in the pdfseparate utility, which is part of the freedesktop Poppler library version 25.04.0. Poppler is a widely used open-source PDF rendering library utilized by many Linux distributions and applications for PDF manipulation and rendering. The vulnerability arises due to an infinite recursion condition triggered when pdfseparate processes a specially crafted PDF file. This infinite recursion leads to excessive consumption of stack memory, ultimately causing a Denial of Service (DoS) by crashing the utility or causing it to hang indefinitely. The vulnerability is classified under CWE-674 (Improper Control of a Resource Through a Recursive Call). The CVSS v3.1 base score is 6.5, indicating a medium severity level. The attack vector is network-based (AV:N), requires no privileges (PR:N), but does require user interaction (UI:R), such as opening or processing a malicious PDF file. The impact is limited to availability, with no confidentiality or integrity compromise. No known exploits are currently reported in the wild, and no patches have been linked yet. This vulnerability affects the pdfseparate utility specifically, which is a command-line tool used to split PDF documents into individual pages, commonly used in automated workflows and document processing pipelines.

For European organizations, the primary impact of this vulnerability is the potential disruption of services that rely on pdfseparate for PDF processing tasks. This includes document management systems, automated reporting tools, and any backend services that manipulate PDFs using Poppler utilities. A successful exploitation can cause denial of service conditions, leading to application crashes or degraded performance, which may interrupt business operations or automated workflows. While the vulnerability does not expose sensitive data or allow code execution, the availability impact can be significant in environments where PDF processing is critical, such as legal, financial, publishing, or government sectors. Additionally, organizations that accept PDFs from external sources or users are at higher risk, as attackers could supply crafted PDFs to trigger the DoS. The requirement for user interaction means that exploitation typically involves a user or system component processing the malicious PDF, which is common in many enterprise environments.

To mitigate this vulnerability, European organizations should first identify all instances where pdfseparate or Poppler utilities are used, especially in automated document processing pipelines. Until an official patch is released, organizations can implement input validation and filtering to block or quarantine suspicious PDF files from untrusted sources. Employ sandboxing or containerization for PDF processing tasks to isolate potential crashes and prevent broader system impact. Monitoring and alerting on abnormal resource usage or crashes of pdfseparate processes can help detect exploitation attempts early. Organizations should also educate users and administrators about the risks of opening or processing untrusted PDF files. Once a patch or updated Poppler version is available, prompt deployment is critical. Additionally, consider alternative PDF processing tools that are not vulnerable or have a better security track record as a temporary workaround. Implementing strict access controls and limiting the exposure of PDF processing services to trusted networks can further reduce risk.