UBUNTU-CVE-2026-102560: Buffer Overflow
A flaw was found in libsoup. When the permessage-deflate WebSocket extension compresses a very large outgoing message, truncated size calculations used for GByteArray growth could wrap, causing zlib to write past the allocated buffer and resulting in a heap buffer overflow.
Affected Software
Event History
Frequently Asked Questions
What conditions are required to trigger the overflow?
An application using libsoup must send a very large outgoing WebSocket message with the permessage-deflate extension enabled. The vulnerable path is reached during compression of that outgoing message.
Which Ubuntu packages are identified as affected?
The affected software listed is ubuntu/libsoup2.4 and ubuntu/libsoup3.
What is the likely impact if the issue is exploited?
The integer wrap can cause zlib to write beyond an allocated heap buffer, resulting in a heap buffer overflow. The provided severity vector indicates network-reachable exploitation without privileges or user interaction, with high availability impact and low confidentiality and integrity impact.