TigerVNC 1.7.1 SMsgReader.cxx readClientCutText) integer overflow

CVSS Meta Temp Score
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CTI Interest Score
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5.2$0-$5k0.00

A vulnerability has been found in TigerVNC 1.7.1 and classified as problematic. Affected by this vulnerability is the function SMsgReader::readClientCutText) of the file SMsgReader.cxx. The manipulation with an unknown input leads to a integer overflow vulnerability. The CWE definition for the vulnerability is CWE-190. The product performs a calculation that can produce an integer overflow or wraparound, when the logic assumes that the resulting value will always be larger than the original value. This can introduce other weaknesses when the calculation is used for resource management or execution control. As an impact it is known to affect availability. The summary by CVE is:

In TigerVNC 1.7.1 (SMsgReader.cxx SMsgReader::readClientCutText), by causing an integer overflow, an authenticated client can crash the server.

The bug was discovered 03/31/2017. The weakness was disclosed 04/01/2017 (GitHub Repository). The advisory is shared at github.com. This vulnerability is known as CVE-2017-7395 since 03/31/2017. The attack can be launched remotely. A single authentication is required for exploitation. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 99239 (Fedora 25 : tigervnc (2017-51979161f4)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Fedora Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 276556 (Fedora Security Update for tigervnc (FEDORA-2017-51979161f4)).

Proper firewalling of is able to address this issue. A possible mitigation has been published 6 days after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (99239). The entries 99155, 99154, 99156 and 99158 are pretty similar.

Productinfo

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Version

CPE 2.3info

CPE 2.2info

CVSSv4info

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CVSSv3info

VulDB Meta Base Score: 5.4
VulDB Meta Temp Score: 5.2

VulDB Base Score: 4.3
VulDB Temp Score: 3.9
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.5
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
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Exploitinginfo

Class: Integer overflow
CWE: CWE-190 / CWE-189
ATT&CK: Unknown

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

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EPSS Percentile: 🔍

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Nessus ID: 99239
Nessus Name: Fedora 25 : tigervnc (2017-51979161f4)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 867773
OpenVAS Name: Fedora Update for tigervnc FEDORA-2017-a66ca10c22
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
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Countermeasuresinfo

Recommended: Firewall
Status: 🔍

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Patch: github.com

Timelineinfo

03/31/2017 🔍
03/31/2017 +0 days 🔍
03/31/2017 +0 days 🔍
03/31/2017 +0 days 🔍
04/01/2017 +1 days 🔍
04/01/2017 +0 days 🔍
04/07/2017 +6 days 🔍
04/07/2017 +0 days 🔍
11/24/2022 +2057 days 🔍

Sourcesinfo

Advisory: RHSA-2017:2000
Status: Not defined
Confirmation: 🔍

CVE: CVE-2017-7395 (🔍)
SecurityFocus: 97305 - TigerVNC Multiple Security Vulnerabilities
OSVDB: - CVE-2017-7395 - TigerVNC - Integer Overflow Issue

See also: 🔍

Entryinfo

Created: 04/01/2017 10:03
Updated: 11/24/2022 12:22
Changes: 04/01/2017 10:03 (80), 11/24/2022 12:22 (5)
Complete: 🔍

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