CVE-2018-20021: canonical ubuntu_linux Infinite Loop
CVSS: 7.8v2.0HighModified
AliasesUBUNTU-CVE-2018-20021DEBIAN-CVE-2018-20021
Published 19-12-2018Last modified 05-08-2024
Vulnerability summary
CVE-2018-20021 is a high (CVSS 7.8) Infinite Loop vulnerability in canonical ubuntu_linux. EPSS estimates a 3.52% chance of exploitation in the next 30 days, higher than 89% of scored vulnerabilities.
CVSS score
7.8/10
010
High · v2.0 (NVD)EPSS score
3.52%
0%100%
Low · 0.00 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded
Advisory lineage
Upstream 0 · Downstream 16 · Related 9Timeline
- 19-12-2018PublishedVulnerability first disclosed.
- 05-08-2024Last modifiedVulnerability information updated.
Description
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
CVSS metrics
4 scores · 3 sources · 2 versionsHigh 7.5Preferred score · NVD (NIST)
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HSourcesAll 3 agree
- OSV · UbuntuEcosystem advisory · calculated7.5HighCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated7.5HighCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
High 7.8Preferred score · NVD (NIST)
AV:N/AC:L/Au:N/C:N/I:N/A:CSourcesSingle source
EPSS trend
Probability
3.52%
Chance of exploitation in the next 30 days
Percentile
89%
Versus all other CVEs
30-day change
0.00 pp
From 3.52% on 18-09-2026
18-09-202618-10-2026
EPSS score3.52%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Debian5 products
- libvncserver< 0.9.11+dfsg-1.2
- ssvnc< 1.0.29-5
- tightvnc< 1:1.3.9-9.1
- veyon< 4.1.4+repack1-1
- debian_linuxEOL8.0 | 9.0
Ubuntu4 products
- italc< 1:2.0.2+dfsg1-4ubuntu0.1 | < 1:3.0.3+dfsg1-3ubuntu0.1
- libvncserver< 0.9.9+dfsg-1ubuntu1.4 | < 0.9.10+dfsg-3ubuntu0.16.04.3 | < 0.9.11+dfsg-1ubuntu1.1
- ssvnc< 1.0.29-2+deb8u1build0.16.04.1 | All versions (No fix recorded)
- tightvnc< 1.3.9-6.5+deb8u1build0.14.04.1~esm1 | All versions (No fix recorded)
Canonical1 product
- ubuntu_linuxEOL14.04 | 16.04 | 18.04 | 18.10
Libvnc_project1 product
- libvncserver< 0.9.12
4 vendors · 11 products
References
19 links
- lists.debian.org/debian-lts-announce/2018/12/msg00017.htmlMailing ListX Refsource MLISTThird Party Advisory
- ics-cert.kaspersky.com/advisories/klcert-advisories/2018/12/19/klcert-18-031-libvnc-infinite-loop/X Refsource MISCThird Party AdvisoryREPORT