LibVNC out-of-bounds write

CVSS Meta Temp Score
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CTI Interest Score
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8.4$0-$5k0.00

Summaryinfo

A vulnerability was found in LibVNC. It has been classified as critical. This affects an unknown part. This manipulation causes out-of-bounds write. The identification of this vulnerability is CVE-2018-20019. It is possible to initiate the attack remotely. There is no exploit available. It is recommended to apply a patch to fix this issue.

Detailsinfo

A vulnerability has been found in LibVNC (unknown version) and classified as critical. Affected by this vulnerability is an unknown code block. The manipulation with an unknown input leads to a out-of-bounds write vulnerability. The CWE definition for the vulnerability is CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

LibVNC before commit a83439b9fbe0f03c48eb94ed05729cb016f8b72f contains multiple heap out-of-bound write vulnerabilities in VNC client code that can result remote code execution

The bug was discovered 12/19/2018. The weakness was shared 12/19/2018 by Solar Designer (Website). It is possible to read the advisory at ics-cert.kaspersky.com. This vulnerability is known as CVE-2018-20019 since 12/10/2018. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. The technical details are unknown and an exploit is not publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 119877 (Debian DLA-1617-1 : libvncserver security update), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Debian Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 171837 (SUSE Enterprise Linux Security Update for LibVNCServer (SUSE-SU-2019:0060-1)).

Applying the patch a83439b9fbe0f03c48eb94ed05729cb016f8b72f is able to eliminate this problem. A possible mitigation has been published 1 weeks after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (119877) and SecurityFocus (BID 106825†). The entries VDB-128103, VDB-128104, VDB-128120 and VDB-128121 are related to this item. Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Name

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.5
VulDB Meta Temp Score: 8.4

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 9.8
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Out-of-bounds write
CWE: CWE-787 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 119877
Nessus Name: Debian DLA-1617-1 : libvncserver security update
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

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

Patch: a83439b9fbe0f03c48eb94ed05729cb016f8b72f

Timelineinfo

12/10/2018 🔍
12/19/2018 +9 days 🔍
12/19/2018 +0 days 🔍
12/19/2018 +0 days 🔍
12/20/2018 +1 days 🔍
12/26/2018 +6 days 🔍
12/27/2018 +1 days 🔍
01/31/2019 +35 days 🔍
06/19/2023 +1600 days 🔍

Sourcesinfo

Advisory: ssa-390195
Researcher: Solar Designer
Status: Confirmed

CVE: CVE-2018-20019 (🔍)
GCVE (CVE): GCVE-0-2018-20019
GCVE (VulDB): GCVE-100-128119
SecurityFocus: 106825 - LibVNCServer Incomplete Fix Multiple Heap Buffer Overflow Vulnerabilities

See also: 🔍

Entryinfo

Created: 12/20/2018 07:48
Updated: 06/19/2023 20:52
Changes: 12/20/2018 07:48 (71), 04/22/2020 08:04 (5), 06/19/2023 20:45 (4), 06/19/2023 20:52 (1)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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