In TightVNC 1.3.10, there is an integer signedness error and resultant heap-based buffer overflow in InitialiseRFBConnection in rfbproto.c (for the vncviewer component). There is no check on the size given to malloc, e.g., -1 is accepted. This allocates a chunk of size zero, which will give a heap pointer. However, one can send 0xffffffff bytes of data, which can have a DoS impact or lead to remote code execution.

[Vulnerability Type] Buffer Overflow

[Vendor of Product] TightVNC

[Affected Product Code Base] vncviewer – 1.3.10

[Affected Component] file : rfbproto.c, function : InitialiseRFBConnection , line of code : 307

[Attack Type] Remote

[Impact Denial of Service] true

[Attack Vectors] You just need to setup a fake server, to interact with the vulnerable client.

[Discoverer] Maher Azzouzi


Use CVE-2022-23967.


View Github