TigerVNC version prior to 1.10.1 is vulnerable to heap buffer overflow. Vulnerability could be triggered from CopyRectDecoder due to incorrect value checks. Exploitation of this vulnerability could potentially result into remote code execution. This attack appear to be exploitable via network connectivity.
Reference and upstream commit:
Created tigervnc tracking bugs for this issue:
Affects: fedora-all [bug 1789528]
As per upstream " All issues require a successfully authenticated connection though."