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TI-2018-14199 Aliases CVE-2018-20021GHSA-m4r6-9jrx-9hxw

Infinite loop in LibVNC

Priority LOW 39CWE-835Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Will not fix Red Hat: no fix planned

Attack profile from CVSS 3.0 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-835.

Summary

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

Why it matters now

EPSS 0.0342 88th percentileScored 2026-11-07
Fix Will not fix Red Hat: no fix planned

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
—LibVNCcommit c3115350eb8bb635d0fdb4dbbb0d0541f38ed19c—No fix listedCNA
  • LibVNC Vendor— Affected commit c3115350eb8bb635d0fdb4dbbb0d0541f38ed19c Fixed in — No fix listed CNA

CPE configurations NVD · 7

CPEVersionsRoleVendor
cpe:2.3:a:libvnc_project:libvncserver:*:*:*:*:*:*:*:*before 0.9.12VulnerableLibvnc Project
cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:*14.04VulnerableCanonical
cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:*16.04VulnerableCanonical
cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:*18.04VulnerableCanonical
cpe:2.3:o:canonical:ubuntu_linux:18.10:*:*:*:*:*:*:*18.10VulnerableCanonical
cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*8.0VulnerableDebian
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*9.0VulnerableDebian
  • cpe:2.3:a:libvnc_project:libvncserver:*:*:*:*:*:*:*:* Versions before 0.9.12 Vulnerable ·Libvnc Project
  • cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:* Versions 14.04 Vulnerable ·Canonical
  • cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:* Versions 16.04 Vulnerable ·Canonical
  • cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:* Versions 18.04 Vulnerable ·Canonical
  • cpe:2.3:o:canonical:ubuntu_linux:18.10:*:*:*:*:*:*:* Versions 18.10 Vulnerable ·Canonical
  • cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:* Versions 8.0 Vulnerable ·Debian
  • cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* Versions 9.0 Vulnerable ·Debian

Remediation

No fixed version listed by the sources yet.

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

Show 2 more groups
  • Advisory ·

    LibVNC — GLSA-202006-06

    4 records Highest priority Priority MEDIUM 1 MEDIUM, 3 LOW

    Other records, highest priority first

    • TI-2018-14198 Out-of-bounds write in LibVNCPriority MEDIUM 53
    • TI-2018-14202 NULL pointer dereference in LibVNCPriority LOW 39
    • TI-2018-14200 LibVNC before 2f5b2ad1c6c99b1ac6482c95844a84d66bb52838 contains multiple weaknesses…Priority LOW 38
    Show all 4 records → Advisory →
  • Advisory ·

    LibVNC — USN-4547-2

    4 records Highest priority Priority MEDIUM 1 MEDIUM, 3 LOW

    Other records, highest priority first

    • TI-2018-14198 Out-of-bounds write in LibVNCPriority MEDIUM 53
    • TI-2018-14202 NULL pointer dereference in LibVNCPriority LOW 39
    • TI-2018-14200 LibVNC before 2f5b2ad1c6c99b1ac6482c95844a84d66bb52838 contains multiple weaknesses…Priority LOW 38
    Show all 4 records → Advisory →

Vendor assessments

Red Hat

Red Hat rating: Low. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 8AffectedNo fix planned: Will not fix
Not affected: 2 products
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7

Timeline

  1. 2026-10-02 Threatist record created from CVE-2018-20021
  2. 2026-10-03 Alias added: GHSA-m4r6-9jrx-9hxw

References

Advisory 9

Other 3

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences