CVE-2018-20021

highpriority · track · 31EPSS 0.034 · 89 %ileEURUUS
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
3.42% (89th) EPSS
CVSS 7.8 · high
Is it mine?
17 products
Check your exposure
Who says so?
4 sources
cnnvd · enisa_euvd · fstec_bdu · nvd

EPSS · scored 2026-10-27

LibVNC before commit c3115350eb8bb635d0fdb4dbbb0d0541f38ed19c contains a CWE-835: Infinite loop vulnerability in VNC client code. Vulnerability allows attacker to consume excessive amount of resources like CPU and RAM

01

cvss

Technical severity, 0–10. One row per scoring source.

7.8
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.9–7.8

v2.07.8highAV:N/AC:L/Au:N/C:N/I:N/A:Cprimary · NVD / NIST USexploitability 10 · impact 6.9
v3.07.5highCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 3.6
v3.06.9mediumCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)
v3.17.5highAV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · FSTEC (BDU) RU
02

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-835USprimaryCWE-400US
03

affected products (17)

Products and version ranges known to be affected.

04

also known as (4)

Other names and identifiers for this entity.

05

sources

Which sources assert this record, and when.

cnnvdenisa_euvdfstec_bdunvdNVDCVE.orgMITRE
published 2018-12-19modified 2026-06-17
07

references (46)

External citations — patches, advisories, analysis.

scry

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