TightVNC up to 1.3.10 FramebufferUpdate Packet tvnviewer.exe buffer overflow

Summaryinfo

A vulnerability was found in TightVNC. It has been declared as critical. Impacted is an unknown function of the file tvnviewer.exe of the component FramebufferUpdate Packet Handler. Such manipulation leads to buffer overflow. This vulnerability is traded as CVE-2021-42785. The attack may be launched remotely. There is no exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in TightVNC and classified as critical. Affected by this issue is some unknown processing of the file tvnviewer.exe of the component FramebufferUpdate Packet Handler. The manipulation with an unknown input leads to a buffer overflow vulnerability. Using CWE to declare the problem leads to CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. Impacted is confidentiality, integrity, and availability.

The weakness was shared 11/24/2021. This vulnerability is handled as CVE-2021-42785 since 10/21/2021. Technical details are known, but there is no available exploit.

Upgrading to version 2.8.63 eliminates this vulnerability. The advisory contains the following remark:

Fixed a security problem which could allow a specially crafted "evil" server execute code on the viewer machine. Technically, the security issue was caused by a buffer overrun in ZRLE decoder.

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Productinfo

Name

• TightVNC

Version

• 1.2
• 1.2.0
• 1.2.1
• 1.2.2
• 1.2.3
• 1.2.4
• 1.2.5
• 1.2.6
• 1.3.9
• 1.3.10

CPE 2.3info

• 🔍
• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍
• 🔍

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Entryinfo

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