LibVNCServer up to 0.9.10 LibVNCClient rfbproto.c FramebufferUpdate Message memory corruption

EntryHistoryDiffjsonxmlCTI

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
7.9	$0-$5k	0.00

A vulnerability classified as critical has been found in LibVNCServer up to 0.9.10. This affects an unknown part of the file rfbproto.c of the component LibVNCClient. The manipulation as part of a FramebufferUpdate Message leads to a memory corruption vulnerability. CWE is classifying the issue as 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. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

Heap-based buffer overflow in rfbproto.c in LibVNCClient in LibVNCServer before 0.9.11 allows remote servers to cause a denial of service (application crash) or possibly execute arbitrary code via a crafted FramebufferUpdate message containing a subrectangle outside of the client drawing area.

The bug was discovered 12/31/2016. The weakness was disclosed 12/31/2016 (Website). The advisory is shared at debian.org. This vulnerability is uniquely identified as CVE-2016-9941 since 12/13/2016. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. It demands that the victim is doing some kind of user interaction. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 96429 (SUSE SLES11 Security Update : LibVNCServer (SUSE-SU-2017:0104-1)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family SuSE Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 169722 (SUSE Enterprise Linux Security Update for tigervnc (SUSE-SU-2017:0519-1)).

Upgrading to version 0.9.11 eliminates this vulnerability. A possible mitigation has been published 2 weeks after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (96429). Further details are available at seclists.org. The entry 94798 is pretty similar.

Productinfo

Name

LibVNCServer

Version

License

open-source

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.0
VulDB Meta Temp Score: 7.9

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 9.8
NVD Vector: 🔍

CVSSv2info

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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔍
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Exploitinginfo

Class: Memory corruption
CWE: CWE-119
ATT&CK: Unknown

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-Day	unlock	unlock	unlock	unlock
Today	unlock	unlock	unlock	unlock

Nessus ID: 96429
Nessus Name: SUSE SLES11 Security Update : LibVNCServer (SUSE-SU-2017:0104-1)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 703753
OpenVAS Name: Debian Security Advisory DSA 3753-1 (libvncserver - security update)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Upgrade: LibVNCServer 0.9.11
Patch: github.com

Timelineinfo

12/13/2016 🔍
12/31/2016 +18 days 🔍
12/31/2016 +0 days 🔍
12/31/2016 +0 days 🔍
12/31/2016 +0 days 🔍
01/01/2017 +1 days 🔍
01/11/2017 +10 days 🔍
01/12/2017 +1 days 🔍
10/27/2022 +2114 days 🔍

Sourcesinfo

Advisory: USN-4587-1
Status: Not defined
Confirmation: 🔍

CVE: CVE-2016-9941 (🔍)
OVAL: 🔍

SecurityFocus: 95170 - LibVNCServer Multiple Heap Based Buffer Overflow Vulnerabilities

Misc.: 🔍
See also: 🔍

Entryinfo

Created: 01/01/2017 10:25
Updated: 10/27/2022 08:29
Changes: 01/01/2017 10:25 (77), 07/29/2019 11:23 (6), 10/27/2022 08:29 (5)
Complete: 🔍