CVE-2024-22641 is a vulnerability in TCPDF, a widely used PHP library for generating PDF documents, specifically versions 6.6.5 and earlier. The issue arises from the library's handling of SVG files embedded or parsed during PDF generation. TCPDF uses regular expressions to process SVG content, but certain crafted SVG inputs can trigger catastrophic backtracking in these regular expressions, causing excessive CPU consumption and effectively resulting in a denial of service (ReDoS). This vulnerability is exploitable remotely without any authentication or user interaction, as it only requires an attacker to submit a malicious SVG file to an application that uses TCPDF for PDF generation. The vulnerability is classified under CWE-434 (Unrestricted Upload of File with Dangerous Type), highlighting the risk of processing untrusted file inputs. The CVSS v3.1 score is 7.5 (high), reflecting the ease of exploitation and the significant impact on availability, although confidentiality and integrity are not compromised. No patches or official fixes have been released yet, and no active exploitation has been reported. The vulnerability primarily affects web applications and services that accept user-uploaded SVG files or otherwise process SVG content through TCPDF, which is common in document management, reporting, and e-commerce platforms.

For European organizations, this vulnerability poses a significant risk to service availability, particularly for those relying on TCPDF for dynamic PDF generation involving SVG content. Denial of service attacks exploiting this vulnerability could disrupt business operations, degrade user experience, and cause downtime in critical document processing workflows. Sectors such as finance, healthcare, government, and e-commerce, which often generate PDF reports or invoices dynamically, may face operational interruptions. The impact is amplified in environments where SVG uploads are allowed without strict validation or sanitization. While the vulnerability does not directly compromise data confidentiality or integrity, the resulting service outages could indirectly affect business continuity and trust. Additionally, organizations with compliance obligations around uptime and service availability (e.g., under GDPR or sector-specific regulations) may face regulatory scrutiny if disruptions occur. The lack of known exploits provides a window for proactive mitigation, but the ease of exploitation and remote attack vector necessitate urgent attention.

1. Immediately audit all applications using TCPDF to identify if SVG parsing is enabled or if untrusted SVG files are accepted. 2. Implement strict input validation and sanitization for SVG files before processing, using libraries designed to safely parse and clean SVG content. 3. Employ rate limiting and request throttling on endpoints that accept file uploads to reduce the risk of resource exhaustion. 4. Monitor CPU and memory usage patterns for anomalies indicative of ReDoS attacks, and establish alerting mechanisms. 5. Where feasible, disable SVG support in TCPDF or replace SVG inputs with safer image formats. 6. Stay updated with TCPDF releases and apply patches as soon as they become available. 7. Consider deploying Web Application Firewalls (WAFs) with rules to detect and block malicious SVG payloads. 8. Conduct regular security testing, including fuzzing and static analysis, to detect similar vulnerabilities in custom code handling SVG or PDF generation.