CVE-2025-53537: Oisf Libhtp

High severity, CVSS 7.5. EPSS: 0.4% chance of exploitation in the next 30 days.

LibHTP is a security-aware parser for the HTTP protocol and its related bits and pieces. In versions 0.5.50 and below, there is a traffic-induced memory leak that can starve the process of memory, leading to loss of visibility. To workaround this issue, set `suricata.yaml app-layer.protocols.http.libhtp.default-config.lzma-enabled` to false. This issue is fixed in version 0.5.51.

Affected products

• Oisf Libhtp: before 0.5.51 (fixed in 0.5.51)

Published 2025-07-23. Last modified 2026-06-17.