CVE-2019-20840

Severity Score

7.5

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

*SSVC

Descriptions

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.

Se detectó un problema en LibVNCServer versiones anteriores a 0.9.13. La biblioteca libvncserver/ws_decode.c puede conllevar a un bloqueo debido a accesos no alineados en la función hybiReadAndDecode

*Credits: N/A

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Attack Vector

Network

Attack Complexity

Low

Authentication

None

Confidentiality

None

Integrity

None

Availability

Partial

* Common Vulnerability Scoring System

SSVC

Decision:-

Exploitation

Automatable

Tech. Impact

* Organization's Worst-case Scenario

Timeline

2020-06-17 CVE Reserved
2020-06-17 CVE Published
2024-08-05 CVE Updated
2024-10-11 EPSS Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CWE-787: Out-of-bounds Write

CAPEC

References (8)

URL	Tag	Source
https://github.com/LibVNC/libvncserver/compare/LibVNCServer-0.9.12...LibVNCServer-0.9.13	Release Notes

URL	Date	SRC

URL	Date	SRC
https://cert-portal.siemens.com/productcert/pdf/ssa-390195.pdf	2023-11-07
https://github.com/LibVNC/libvncserver/commit/0cf1400c61850065de590d403f6d49e32882fd76	2023-11-07

URL	Date	SRC
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00033.html	2023-11-07
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00055.html	2023-11-07
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00066.html	2023-11-07
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4F6FUH4EFK4NAP6GT4TQRTBKWIRCZLIY	2023-11-07
https://usn.ubuntu.com/4434-1	2023-11-07

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Siemens Search vendor "Siemens"	Simatic Itc1500 Firmware Search vendor "Siemens" for product "Simatic Itc1500 Firmware"	>= 3.0.0.0 < 3.2.1.0 Search vendor "Siemens" for product "Simatic Itc1500 Firmware" and version " >= 3.0.0.0 < 3.2.1.0"	-	Affected	in	Siemens Search vendor "Siemens"	Simatic Itc1500 Search vendor "Siemens" for product "Simatic Itc1500"	-	-	Safe
Siemens Search vendor "Siemens"	Simatic Itc1500 Pro Firmware Search vendor "Siemens" for product "Simatic Itc1500 Pro Firmware"	>= 3.0.0.0 < 3.2.1.0 Search vendor "Siemens" for product "Simatic Itc1500 Pro Firmware" and version " >= 3.0.0.0 < 3.2.1.0"	-	Affected	in	Siemens Search vendor "Siemens"	Simatic Itc1500 Pro Search vendor "Siemens" for product "Simatic Itc1500 Pro"	-	-	Safe
Siemens Search vendor "Siemens"	Simatic Itc1900 Firmware Search vendor "Siemens" for product "Simatic Itc1900 Firmware"	>= 3.0.0.0 < 3.2.1.0 Search vendor "Siemens" for product "Simatic Itc1900 Firmware" and version " >= 3.0.0.0 < 3.2.1.0"	-	Affected	in	Siemens Search vendor "Siemens"	Simatic Itc1900 Search vendor "Siemens" for product "Simatic Itc1900"	-	-	Safe
Siemens Search vendor "Siemens"	Simatic Itc1900 Pro Firmware Search vendor "Siemens" for product "Simatic Itc1900 Pro Firmware"	>= 3.0.0.0 < 3.2.1.0 Search vendor "Siemens" for product "Simatic Itc1900 Pro Firmware" and version " >= 3.0.0.0 < 3.2.1.0"	-	Affected	in	Siemens Search vendor "Siemens"	Simatic Itc1900 Pro Search vendor "Siemens" for product "Simatic Itc1900 Pro"	-	-	Safe
Siemens Search vendor "Siemens"	Simatic Itc2200 Firmware Search vendor "Siemens" for product "Simatic Itc2200 Firmware"	>= 3.0.0.0 < 3.2.1.0 Search vendor "Siemens" for product "Simatic Itc2200 Firmware" and version " >= 3.0.0.0 < 3.2.1.0"	-	Affected	in	Siemens Search vendor "Siemens"	Simatic Itc2200 Search vendor "Siemens" for product "Simatic Itc2200"	-	-	Safe
Siemens Search vendor "Siemens"	Simatic Itc2200 Pro Firmware Search vendor "Siemens" for product "Simatic Itc2200 Pro Firmware"	>= 3.0.0.0 < 3.2.1.0 Search vendor "Siemens" for product "Simatic Itc2200 Pro Firmware" and version " >= 3.0.0.0 < 3.2.1.0"	-	Affected	in	Siemens Search vendor "Siemens"	Simatic Itc2200 Pro Search vendor "Siemens" for product "Simatic Itc2200 Pro"	-	-	Safe
Libvnc Project Search vendor "Libvnc Project"		Libvncserver Search vendor "Libvnc Project" for product "Libvncserver"				<= 0.9.12 Search vendor "Libvnc Project" for product "Libvncserver" and version " <= 0.9.12"		-		Affected
Canonical Search vendor "Canonical"		Ubuntu Linux Search vendor "Canonical" for product "Ubuntu Linux"				14.04 Search vendor "Canonical" for product "Ubuntu Linux" and version "14.04"		lts		Affected
Canonical Search vendor "Canonical"		Ubuntu Linux Search vendor "Canonical" for product "Ubuntu Linux"				16.04 Search vendor "Canonical" for product "Ubuntu Linux" and version "16.04"		esm		Affected
Canonical Search vendor "Canonical"		Ubuntu Linux Search vendor "Canonical" for product "Ubuntu Linux"				16.04 Search vendor "Canonical" for product "Ubuntu Linux" and version "16.04"		lts		Affected
Canonical Search vendor "Canonical"		Ubuntu Linux Search vendor "Canonical" for product "Ubuntu Linux"				18.04 Search vendor "Canonical" for product "Ubuntu Linux" and version "18.04"		lts		Affected
Canonical Search vendor "Canonical"		Ubuntu Linux Search vendor "Canonical" for product "Ubuntu Linux"				18.10 Search vendor "Canonical" for product "Ubuntu Linux" and version "18.10"		-		Affected
Canonical Search vendor "Canonical"		Ubuntu Linux Search vendor "Canonical" for product "Ubuntu Linux"				20.04 Search vendor "Canonical" for product "Ubuntu Linux" and version "20.04"		lts		Affected
Debian Search vendor "Debian"		Debian Linux Search vendor "Debian" for product "Debian Linux"				8.0 Search vendor "Debian" for product "Debian Linux" and version "8.0"		-		Affected
Debian Search vendor "Debian"		Debian Linux Search vendor "Debian" for product "Debian Linux"				9.0 Search vendor "Debian" for product "Debian Linux" and version "9.0"		-		Affected
Opensuse Search vendor "Opensuse"		Leap Search vendor "Opensuse" for product "Leap"				15.2 Search vendor "Opensuse" for product "Leap" and version "15.2"		-		Affected