01 Record

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.

UnratedPUBLISHEDCNA: mitre

CNA base scoreUnratedNo CNA CVSS vector

View raw JSON

02 Description

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.

03 Exploitation and scoring

Exploitation: Not assessed. CISA has not published an exploitation assessment for this record, and it is not in the KEV catalog. That is an absence of assessment, not a finding of no risk.
SSVC decision: Not assessed by CISA
EPSS probability: 2.61% probability of exploitation activity in the next 30 days.
EPSS percentile: Ranks above 84.1% of scored records. A rank, not a probability.
NVD base score: 7.5 (CVSS v3.x), scored by the NVD independently of the CNA.
NVD CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD analysis status: Modified. NVD last modified this record on 2026-06-17.
Red Hat severity: Moderate. Red Hat's rating for its own products, not a CVSS rating.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

04 Metadata

Published

2020-06-17 15:11Z6 YR AGO

Last updated

2024-08-05 02:53Z2 YR AGO

Reserved

2020-06-17

Assigning CNA

mitre

Record state

PUBLISHED

Severity

Not rated by the issuing CNA

CNA CVSS vector

Not published by the issuing CNA

Weaknesses

CWE-787Out-of-bounds WriteBase
CWE-119Improper Restriction of Operations within the Bounds of a Memory BufferClass

Data version

5.1

Document digest

a4f8623ce97cd198b2fb01aff8eeb99ea6774100e9b7ec1a822c838173840481

05 Affected products

VendorProductVersionsPlatforms

canonicalubuntu_linuxNot specified—

debiandebian_linuxNot specified—

libvnc_projectlibvncserverNot specified—

opensuseleapNot specified—

redhatenterprise_linuxNot specified—

siemenssimatic_itc1500Not specified—

siemenssimatic_itc1500_firmwareNot specified—

siemenssimatic_itc1500_proNot specified—

siemenssimatic_itc1500_pro_firmwareNot specified—

siemenssimatic_itc1900Not specified—

siemenssimatic_itc1900_firmwareNot specified—

siemenssimatic_itc1900_proNot specified—

siemenssimatic_itc1900_pro_firmwareNot specified—

siemenssimatic_itc2200Not specified—

siemenssimatic_itc2200_firmwareNot specified—

siemenssimatic_itc2200_proNot specified—

siemenssimatic_itc2200_pro_firmwareNot specified—

06 References

github.comhttps://github.com/LibVNC/libvncserver/compare/LibVNCServer-0.9.12...LibVNCServer-0.9.13x_refsource_MISC
github.comhttps://github.com/LibVNC/libvncserver/commit/0cf1400c61850065de590d403f6d49e32882fd76x_refsource_MISC
lists.fedoraproject.orgFEDORA-2020-1a4b1c8271https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4F6FUH4EFK4NAP6GT4TQRTBKWIRCZLIY/vendor-advisoryx_refsource_FEDORA
lists.opensuse.orgopenSUSE-SU-2020:0988http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00033.htmlvendor-advisoryx_refsource_SUSE
lists.opensuse.orgopenSUSE-SU-2020:1025http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00055.htmlvendor-advisoryx_refsource_SUSE
lists.opensuse.orgopenSUSE-SU-2020:1056http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00066.htmlvendor-advisoryx_refsource_SUSE
usn.ubuntu.comUSN-4434-1https://usn.ubuntu.com/4434-1/vendor-advisoryx_refsource_UBUNTU
cert-portal.siemens.comhttps://cert-portal.siemens.com/productcert/pdf/ssa-390195.pdfx_refsource_CONFIRM

01 Record index

CVE-2019-20840

02 Description

03 Exploitation and scoring

04 Metadata

05 Affected products

06 References

02 Records

CVE-2019-20840

02 Description

03 Exploitation and scoring

04 Metadata

05 Affected products

06 References