A vulnerability was found in UltraVNC Revision 1203 (Connectivity Software) and classified as critical. Affected by this issue is an unknown code block of the component Client Ultra Decoder. The manipulation with an unknown input leads to a memory corruption vulnerability. Using CWE to declare the problem leads to CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. Impacted is confidentiality, integrity, and availability. CVE summarizes:

UltraVNC revision 1203 has multiple heap buffer overflow vulnerabilities in VNC client code inside Ultra decoder, which results in code execution. This attack appears to be exploitable via network connectivity. These vulnerabilities have been fixed in revision 1204.

The bug was discovered 03/01/2019. The weakness was published 03/05/2019. This vulnerability is handled as CVE-2019-8262 since 02/12/2019. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. There are neither technical details nor an exploit publicly available.

The vulnerability was handled as a non-public zero-day exploit for at least 4 days. During that time the estimated underground price was around $0-$5k. The commercial vulnerability scanner Qualys is able to test this issue with plugin 371706 (UltraVNC Multiple Code Execution Vulnerabilities).

Applying the patch Revision 1204 is able to eliminate this problem.

Similar entries are available at 131316, 131356, 131357 and 131358.

Productinfo

Type

• Connectivity Software

Name

• UltraVNC

Version

• Revision 1203

License

• open-source

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CPE 2.2info

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