CVE-2019-8268 Memory corruption in UltraVNC

Critical 9.8 Published 9 Mar 2019 Updated 17 Sep 2024

An attacker can execute arbitrary code on UltraVNC clients via network connectivity due to off-by-one errors in string reading functions.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: None listed

What is CVE-2019-8268?

CVE-2019-8268 is a critical memory corruption vulnerability in Kaspersky Lab UltraVNC, published on 9 Mar 2019. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

UltraVNC revision 1206 has multiple off-by-one vulnerabilities in VNC client code connected with improper usage of ClientConnection::ReadString function, which can potentially result code execution. This attack appears to be exploitable via network connectivity. These vulnerabilities have been fixed in revision 1207.

Weakness: CWE-193

Which versions are affected by CVE-2019-8268?

It affects 4 products.

Products include Siemens Sinumerik Access Mymachine\/P2p, Siemens Sinumerik Pcu Base Win10 Software\/Ipc, Siemens Sinumerik Pcu Base Win7 Software\/Ipc, Uvnc Ultravnc.

How do I fix CVE-2019-8268?

No fix has been published for CVE-2019-8268 yet. Limit exposure of the affected software until one is available.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2019-8268 being exploited?

There is no known exploitation of CVE-2019-8268 in the wild and no public exploit code.

Sources

Also known as GHSA-h835-4p8w-83c9.