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CVE-2019-20840

An issue was discovered in LibVNCServer before 0.9.13. libvncserver/ws_decode.c can lead to a crash because of unaligned accesses in hybiReadAndDecode.

Published: Jun 17, 2020Updated: Nov 21, 2024 Sources: CVE List NVD csafCWE-787
NVD MITRE
7.5CVSSHIGH
EPSS Score
2.6%
Top 16.7%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available

Description

Multiple LibVNC vulnerabilities in the affected products listed below could allow remote code execution, information disclosure and Denial-of-Service attacks under certain conditions. Siemens has released updates for the affected products and recommends to update to the latest versions.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:NI:NA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:NIntegrity
None
A:HAvailability
High
Open in CVSS calculator →

Weaknesses

CWE-787

Affected Products

n/an/a
libvncserverlibvnc project
Mixed
Communications / messaging-chat
ubuntu linuxcanonical
On-premOS
Operating Systems / linux-distro
debian linuxdebian
On-premOS
Operating Systems / linux-distro
simatic itc1500 firmwaresiemens
EmbeddedFirmware
ICS / OT / IoT / industrial-network
libvnc projectoss-projectCommunicationsaka libvncserver, libvnc-server, vnc server
canonicalcommercialGBOperating Systemsaka canonical ltd.
debianoss-projectGBOperating Systemsaka debian gnu/linux
siemenscommercialDEEnterprise Softwareaka siemens ag
and 6 more affected products View all →

Attack Graph

Products CVE Techniques Tactics

Click technique nodes to view MITRE ATT&CK details. Scroll to zoom, drag to pan.

Exploitability

Official Patch Available

MITRE ATT&CK

2 techniques
Initial Access
Privilege Escalation
View detailed technique mapping

References

https://cert-portal.siemens.com/productcert/csaf/ssa-390195.json
cert-portal.siemens.com
https://cert-portal.siemens.com/productcert/txt/ssa-390195.txt
cert-portal.siemens.com
https://cert-portal.siemens.com/productcert/pdf/ssa-390195.pdf
cert-portal.siemens.com
and 35 more references View all →

Timeline

Published
Jun 17, 2020
Last Updated
Nov 21, 2024

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