CVE-2026-102559

HIGH CVSS 3.1: 8.6
Updated Sep 30, 2026
Payload
Parameter Value
CVSS 8.6 (HIGH)
Type CWE-125 (Out-of-bounds Read)
Vendor Payload
Public PoC No

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.

Attack Parameters

Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Privileges Required
None
No privileges needed
User Interaction
None
No user interaction needed

Impact Assessment

Confidentiality
Low
Partial data leak
Integrity
Low
Partial data modification
Availability
High
Complete denial of service

CVSS Vector v3.1

Weakness Type (CWE)