libsoup, an HTTP client/server library for GNOME, has multiple security flaws related to WebSocket frame handling. These include improper signal emission causing heap corruption or crash (CVE-2026-102556), inadequate size capping during fragmented message reassembly leading to heap corruption or crash (CVE-2026-102557), and a heap buffer overflow when constructing masked client frames with large payloads (CVE-2026-102559). These vulnerabilities affect versions prior to 2.74.3-31.oe2403sp3 and have been assigned a high severity score.