---
cve: "CVE-2018-20021"
severity: "HIGH"
cvss: 7.5
epss: "3.5%"
vendor: "n/a"
kev: false
exploited: false
published: "2018-12-19 16:29:00"
tags: [cve, security, high]
source: tsecurity.de CVE-Dossier
exported: "2026-10-28T15:11:37+01:00"
---

# CVE-2018-20021

> 7.5 HIGH

## Beschreibung

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

## CNA-Record (Kanon, cvelistV5)

- CNA: **Kaspersky**
- State: PUBLISHED
- Stand: 2024-08-05 11:51:18

## CVSS-Vektor

```
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Gering | bad |
| PR Privilegien | Keine | bad |
| UI Interaktion | Keine | bad |
| S Scope | Unverändert | good |
| C Vertraulichkeit | Keine | good |
| I Integrität | Keine | good |
| A Verfügbarkeit | Hoch | bad |

## Schwachstellen-Klasse

- **CWE-835** — Loop with Unreachable Exit Condition ('Infinite Loop')
  The product contains an iteration or loop with an exit condition that cannot be reached, i.e., an infinite loop.

## Patch verfügbar (OSV)

- 0a70095271d845d16a3ed17354841b01f33963ad (Commit)

## Referenzen

- <https://www.debian.org/security/2019/dsa-4383>
- <https://lists.debian.org/debian-lts-announce/2018/12/msg00017.html>
- <https://ics-cert.kaspersky.com/advisories/klcert-advisories/2018/12/19/klcert-18-031-libvnc-infinite-loop/>
- <https://usn.ubuntu.com/3877-1/>
- <https://security.gentoo.org/glsa/201908-05>
- <https://lists.debian.org/debian-lts-announce/2019/10/msg00042.html>
- <https://lists.debian.org/debian-lts-announce/2019/11/msg00033.html>
- <https://lists.debian.org/debian-lts-announce/2019/12/msg00028.html>
- <https://security.gentoo.org/glsa/202006-06>
- <https://usn.ubuntu.com/4547-1/>
- <https://usn.ubuntu.com/4547-2/>
- <https://usn.ubuntu.com/4587-1/>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/sicherheitsluecken/cve-2018-20021/) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI WID (CSAF)_