libxml2, possibly before 2.5.0, does not properly detect recursion during entity expansion, which allows context-dependent attackers to cause a denial of service (memory and CPU consumption) via a crafted XML document containing a large number of nested entity references, aka the "billion laughs attack."
This vulnerability carries a MEDIUM severity rating with a CVSS v3.1 score of 6.5, indicating it can be exploited remotely over the network with relatively low complexity though user interaction is required and does not require pre-existing privileges . The vulnerability impacts and availability (service disruption) for affected systems. Impacting 1 product from xmlsoft organizations running these solutions should prioritize assessment and patching.
Originally identified in 2003, this vulnerability predates many modern security frameworks and practices. The vulnerability landscape of that era was characterized by different threat models and less mature defense mechanisms compared to contemporary standards.
2003-12-31T05:00:00.000
2026-04-16T00:27:16.627
Modified
CVSSv3.1: 6.5 (MEDIUM)
AV:N/AC:M/Au:N/C:C/I:C/A:C
8.6
10.0
SecUtils normalizes and enriches National Vulnerability Database (NVD) records by standardizing vendor and product identifiers, aggregating vulnerability metadata from both NVD and MITRE sources, and providing structured context for security teams. For xmlsoft's affected products, we extract Common Platform Enumeration (CPE) data, Common Weakness Enumeration (CWE) classifications, CVSS severity metrics, and reference data to enable rapid vulnerability prioritization and asset correlation. This record contains no exploit code, proof-of-concept instructions, or attack methodologies—only defensive intelligence necessary for patch management, risk assessment, and security operations.