LibVNCServer up to 0.9.11 WebSocket Frame websockets.c out-of-bounds write

Summaryinfo

A vulnerability classified as critical has been found in LibVNCServer up to 0.9.11. This impacts an unknown function of the file websockets.c of the component WebSocket Frame Handler. The manipulation leads to out-of-bounds write. This vulnerability is listed as CVE-2017-18922. The attack may be initiated remotely. There is no available exploit. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in LibVNCServer up to 0.9.11 and classified as very critical. This issue affects some unknown processing of the file websockets.c of the component WebSocket Frame Handler. The manipulation with an unknown input leads to a out-of-bounds write vulnerability. Using CWE to declare the problem leads to CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

It was discovered that websockets.c in LibVNCServer prior to 0.9.12 did not properly decode certain WebSocket frames. A malicious attacker could exploit this by sending specially crafted WebSocket frames to a server, causing a heap-based buffer overflow.

The weakness was presented 04/22/2023. The advisory is shared at github.com. The identification of this vulnerability is CVE-2017-18922 since 06/30/2020. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details are known, but no exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 04/22/2023).

Upgrading to version 0.9.12 eliminates this vulnerability. Applying the patch aac95a9dcf4bbba87b76c72706c3221a842ca433 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Name

• LibVNCServer

Version

• 0.9.0
• 0.9.1
• 0.9.2
• 0.9.3
• 0.9.4
• 0.9.5
• 0.9.6
• 0.9.7
• 0.9.8
• 0.9.9
• 0.9.10
• 0.9.11

License

• open-source

CPE 2.3info

• 🔍
• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍
• 🔍

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Entryinfo

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