MajorCritical vulnerability

CVE-2026-102559 (CVSS 8.6)

NVD · officialPublished Sep 29, 2026Risk 37/100

A flaw was found in libsoup. When constructing a masked WebSocket client frame for a very large outgoing payload, size values passed to GByteArray allocation APIs could be truncated while the masking routine still used the full length, causing a heap buffer overflow.

Technical details

CVSS

8.6

AV:NetworkAC:LowPR:NoneUI:NoneC:LowI:LowA:High

Evidence and sources

This record is attributed to NVD. Exploitation status and remediation guidance are kept separate from the vulnerability's technical severity.

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