CVE-2024-22368 is a medium-severity vulnerability affecting the Perl module Spreadsheet::ParseXLSX versions prior to 0.28. This module is used to parse XLSX spreadsheet files. The vulnerability arises due to an out-of-memory (OOM) condition triggered when parsing a specially crafted XLSX document. The root cause is linked to the module's memoization implementation, which does not properly constrain the handling of merged cells within the spreadsheet. Specifically, the memoize function, intended to optimize repeated computations, can be manipulated by an attacker to cause excessive memory allocation when processing merged cells. This can lead to resource exhaustion on the host system, potentially causing the parsing process to crash or become unresponsive. The CVSS v3.1 base score is 5.5 (medium), with vector AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H, indicating that the attack requires local access, low attack complexity, no privileges, and user interaction, with impact limited to availability (denial of service) but no confidentiality or integrity compromise. There are no known exploits in the wild at this time, and no vendor or product specifics beyond the Perl module are provided. No patches or mitigations have been explicitly linked yet, but upgrading to version 0.28 or later presumably addresses the issue.

For European organizations, the primary impact of this vulnerability is a denial-of-service condition on systems that process XLSX files using the vulnerable Perl module. Organizations that rely on automated or manual parsing of Excel spreadsheets in Perl environments—such as data processing pipelines, reporting tools, or internal applications—may experience service disruptions or crashes if maliciously crafted XLSX files are introduced. This could affect availability of critical business functions, especially in sectors handling large volumes of spreadsheet data like finance, logistics, or government agencies. Since exploitation requires local access and user interaction (opening or processing the crafted file), the risk is somewhat mitigated by controlled environments and user training. However, insider threats or phishing attacks delivering malicious XLSX files could trigger the vulnerability. The lack of confidentiality or integrity impact reduces the risk of data breaches or manipulation, but availability disruptions could still cause operational delays and reputational damage.

To mitigate CVE-2024-22368, European organizations should: 1) Identify and inventory all systems and applications using the Spreadsheet::ParseXLSX Perl module, especially those handling untrusted XLSX files. 2) Upgrade the module to version 0.28 or later where the vulnerability is fixed. 3) Implement strict input validation and sandboxing for XLSX file processing to limit resource consumption and isolate parsing processes. 4) Employ endpoint security controls to prevent execution of untrusted or suspicious XLSX files, including email filtering and user awareness training to reduce the risk of opening malicious documents. 5) Monitor system resource usage and application logs for signs of abnormal memory consumption or crashes related to XLSX parsing. 6) Where possible, restrict local access to systems performing XLSX parsing to trusted personnel only, minimizing the attack surface. These steps go beyond generic advice by focusing on module-specific upgrades, process isolation, and user behavior controls.