CVE catalog
CVE-2018-20021
libvncserver: CVE-2018-20021
- Severity
- Medium · CVSS 6.5
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H - Published
- Source
- [NVD] · [CVE record]
- EPSS
- 3.42% · Oct 25, 2026
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
Vulnerable and fixed packages
Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.
| Distribution | Package | Release | Version | Status |
|---|---|---|---|---|
| Debian | ssvnc | sid | 1.0.29-7 | fixed |
| Debian | ssvnc | forky | 1.0.29-7 | fixed |
| Debian | ssvnc | trixie | 1.0.29-6.1 | fixed |
| Debian | ssvnc | bookworm | 1.0.29-6 | fixed |
| Debian | veyon | sid | 4.9.7+repack1-1.1 | fixed |
| Debian | veyon | trixie | 4.9.5+repack1-2 | fixed |
| Debian | veyon | bookworm | 4.7.5+repack1-1 | fixed |
| Debian | tightvnc | sid | 1:1.3.10-11 | fixed |
| Debian | tightvnc | forky | 1:1.3.10-11 | fixed |
| Debian | tightvnc | trixie | 1:1.3.10-9 | fixed |
| Debian | tightvnc | bookworm | 1:1.3.10-7 | fixed |
| Debian | libvncserver | sid | 0.9.15+dfsg-6 | fixed |
| Debian | libvncserver | forky | 0.9.15+dfsg-6 | fixed |
| Debian | libvncserver | trixie | 0.9.15+dfsg-1+deb13u2 | fixed |
| Debian | libvncserver | bookworm | 0.9.14+dfsg-1+deb12u2 | fixed |
Fixed-version evidence
| Distribution | Package | Type | Release | Fixed version | Urgency | Origin | Bugs |
|---|---|---|---|---|---|---|---|
| Debian | ssvnc | source | sid | 1.0.29-5 | not yet assigned | Not reported | [945827] |
| Debian | ssvnc | source | forky | 1.0.29-5 | not yet assigned | Not reported | [945827] |
| Debian | ssvnc | source | trixie | 1.0.29-5 | not yet assigned | Not reported | [945827] |
| Debian | ssvnc | source | bookworm | 1.0.29-5 | not yet assigned | Not reported | [945827] |
| Debian | veyon | source | sid | 4.1.4+repack1-1 | not yet assigned | Not reported | Not reported |
| Debian | veyon | source | trixie | 4.1.4+repack1-1 | not yet assigned | Not reported | Not reported |
| Debian | veyon | source | bookworm | 4.1.4+repack1-1 | not yet assigned | Not reported | Not reported |
| Debian | tightvnc | source | sid | 1:1.3.9-9.1 | not yet assigned | Not reported | Not reported |
| Debian | tightvnc | source | forky | 1:1.3.9-9.1 | not yet assigned | Not reported | Not reported |
| Debian | tightvnc | source | trixie | 1:1.3.9-9.1 | not yet assigned | Not reported | Not reported |
| Debian | tightvnc | source | bookworm | 1:1.3.9-9.1 | not yet assigned | Not reported | Not reported |
| Debian | libvncserver | source | sid | 0.9.11+dfsg-1.2 | not yet assigned | Not reported | [916941] |
| Debian | libvncserver | source | forky | 0.9.11+dfsg-1.2 | not yet assigned | Not reported | [916941] |
| Debian | libvncserver | source | trixie | 0.9.11+dfsg-1.2 | not yet assigned | Not reported | [916941] |
| Debian | libvncserver | source | bookworm | 0.9.11+dfsg-1.2 | not yet assigned | Not reported | [916941] |
OpenFactory catalog packages
[Debian 12 (Bookworm)]
- [libveyon-core]Fixed
Source package: [veyon]
Details (2)
4.7.5+repack1-1· amd64 · bookwormFixed · Fixed:
4.1.4+repack1-1dsa · veyon · debian · bookworm; dsa · veyon · debian · 12
4.7.5+repack1-1· arm64 · bookwormFixed · Fixed:
4.1.4+repack1-1dsa · veyon · debian · bookworm; dsa · veyon · debian · 12
- [libvncclient1]Fixed
Source package: [libvncserver]
Details (2)
0.9.14+dfsg-1+deb12u2· amd64 · bookwormFixed · Fixed:
0.9.11+dfsg-1.2dsa · libvncserver · debian · bookworm; dsa · libvncserver · debian · 12
0.9.14+dfsg-1+deb12u2· arm64 · bookwormFixed · Fixed:
0.9.11+dfsg-1.2dsa · libvncserver · debian · bookworm; dsa · libvncserver · debian · 12
- [libvncserver1]Fixed
Source package: [libvncserver]
Details (2)
0.9.14+dfsg-1+deb12u2· amd64 · bookwormFixed · Fixed:
0.9.11+dfsg-1.2dsa · libvncserver · debian · bookworm; dsa · libvncserver · debian · 12
0.9.14+dfsg-1+deb12u2· arm64 · bookwormFixed · Fixed:
0.9.11+dfsg-1.2dsa · libvncserver · debian · bookworm; dsa · libvncserver · debian · 12
- [libvncserver-dev]Fixed
Source package: [libvncserver]
Details (2)
0.9.14+dfsg-1+deb12u2· amd64 · bookwormFixed · Fixed:
0.9.11+dfsg-1.2dsa · libvncserver · debian · bookworm; dsa · libvncserver · debian · 12
0.9.14+dfsg-1+deb12u2· arm64 · bookwormFixed · Fixed:
0.9.11+dfsg-1.2dsa · libvncserver · debian · bookworm; dsa · libvncserver · debian · 12
- [ssvnc]Fixed
Source package: [ssvnc]
Details (2)
1.0.29-6+b1· amd64 · bookwormFixed · Fixed:
1.0.29-5dsa · ssvnc · debian · bookworm; dsa · ssvnc · debian · 12
1.0.29-6+b1· arm64 · bookwormFixed · Fixed:
1.0.29-5dsa · ssvnc · debian · bookworm; dsa · ssvnc · debian · 12
- [tightvncpasswd]Fixed
Source package: [tightvnc]
Details (2)
1:1.3.10-7· amd64 · bookwormFixed · Fixed:
1:1.3.9-9.1dsa · tightvnc · debian · bookworm; dsa · tightvnc · debian · 12
1:1.3.10-7· arm64 · bookwormFixed · Fixed:
1:1.3.9-9.1dsa · tightvnc · debian · bookworm; dsa · tightvnc · debian · 12
- [tightvncserver]Fixed
Source package: [tightvnc]
Details (2)
1:1.3.10-7· amd64 · bookwormFixed · Fixed:
1:1.3.9-9.1dsa · tightvnc · debian · bookworm; dsa · tightvnc · debian · 12
1:1.3.10-7· arm64 · bookwormFixed · Fixed:
1:1.3.9-9.1dsa · tightvnc · debian · bookworm; dsa · tightvnc · debian · 12
- [veyon-configurator]Fixed
Source package: [veyon]
Details (2)
4.7.5+repack1-1· amd64 · bookwormFixed · Fixed:
4.1.4+repack1-1dsa · veyon · debian · bookworm; dsa · veyon · debian · 12
4.7.5+repack1-1· arm64 · bookwormFixed · Fixed:
4.1.4+repack1-1dsa · veyon · debian · bookworm; dsa · veyon · debian · 12
- [veyon-master]Fixed
Source package: [veyon]
Details (2)
4.7.5+repack1-1· amd64 · bookwormFixed · Fixed:
4.1.4+repack1-1dsa · veyon · debian · bookworm; dsa · veyon · debian · 12
4.7.5+repack1-1· arm64 · bookwormFixed · Fixed:
4.1.4+repack1-1dsa · veyon · debian · bookworm; dsa · veyon · debian · 12
- [veyon-plugins]Fixed
Source package: [veyon]
Details (2)
4.7.5+repack1-1· amd64 · bookwormFixed · Fixed:
4.1.4+repack1-1dsa · veyon · debian · bookworm; dsa · veyon · debian · 12
4.7.5+repack1-1· arm64 · bookwormFixed · Fixed:
4.1.4+repack1-1dsa · veyon · debian · bookworm; dsa · veyon · debian · 12
- [veyon-service]Fixed
Source package: [veyon]
Details (2)
4.7.5+repack1-1· amd64 · bookwormFixed · Fixed:
4.1.4+repack1-1dsa · veyon · debian · bookworm; dsa · veyon · debian · 12
4.7.5+repack1-1· arm64 · bookwormFixed · Fixed:
4.1.4+repack1-1dsa · veyon · debian · bookworm; dsa · veyon · debian · 12
- [xtightvncviewer]Fixed
Source package: [tightvnc]
Details (2)
1:1.3.10-7· amd64 · bookwormFixed · Fixed:
1:1.3.9-9.1dsa · tightvnc · debian · bookworm; dsa · tightvnc · debian · 12
1:1.3.10-7· arm64 · bookwormFixed · Fixed:
1:1.3.9-9.1dsa · tightvnc · debian · bookworm; dsa · tightvnc · debian · 12
[Debian 13 (Trixie)]
- [libveyon-core]Fixed
Source package: [veyon]
Details (2)
4.9.5+repack1-2· amd64 · trixieFixed · Fixed:
4.1.4+repack1-1dsa · veyon · debian · 13
4.9.5+repack1-2· arm64 · trixieFixed · Fixed:
4.1.4+repack1-1dsa · veyon · debian · 13
- [libvncclient1]Fixed
Source package: [libvncserver]
Details (2)
0.9.15+dfsg-1+deb13u2· amd64 · trixieFixed · Fixed:
0.9.11+dfsg-1.2dsa · libvncserver · debian · 13
0.9.15+dfsg-1+deb13u2· arm64 · trixieFixed · Fixed:
0.9.11+dfsg-1.2dsa · libvncserver · debian · 13
- [libvncserver1]Fixed
Source package: [libvncserver]
Details (2)
0.9.15+dfsg-1+deb13u2· amd64 · trixieFixed · Fixed:
0.9.11+dfsg-1.2dsa · libvncserver · debian · 13
0.9.15+dfsg-1+deb13u2· arm64 · trixieFixed · Fixed:
0.9.11+dfsg-1.2dsa · libvncserver · debian · 13
- [libvncserver-dev]Fixed
Source package: [libvncserver]
Details (2)
0.9.15+dfsg-1+deb13u2· amd64 · trixieFixed · Fixed:
0.9.11+dfsg-1.2dsa · libvncserver · debian · 13
0.9.15+dfsg-1+deb13u2· arm64 · trixieFixed · Fixed:
0.9.11+dfsg-1.2dsa · libvncserver · debian · 13
- [ssvnc]Fixed
Details (2)
1.0.29-6.1· amd64 · trixieFixed · Fixed:
1.0.29-5dsa · ssvnc · debian · 13
1.0.29-6.1· arm64 · trixieFixed · Fixed:
1.0.29-5dsa · ssvnc · debian · 13
- [tightvncpasswd]Fixed
Source package: [tightvnc]
Details (2)
1:1.3.10-9· amd64 · trixieFixed · Fixed:
1:1.3.9-9.1dsa · tightvnc · debian · 13
1:1.3.10-9+b1· arm64 · trixieFixed · Fixed:
1:1.3.9-9.1dsa · tightvnc · debian · 13
- [tightvncserver]Fixed
Source package: [tightvnc]
Details (2)
1:1.3.10-9· amd64 · trixieFixed · Fixed:
1:1.3.9-9.1dsa · tightvnc · debian · 13
1:1.3.10-9+b1· arm64 · trixieFixed · Fixed:
1:1.3.9-9.1dsa · tightvnc · debian · 13
- [veyon-configurator]Fixed
Source package: [veyon]
Details (2)
4.9.5+repack1-2· amd64 · trixieFixed · Fixed:
4.1.4+repack1-1dsa · veyon · debian · 13
4.9.5+repack1-2· arm64 · trixieFixed · Fixed:
4.1.4+repack1-1dsa · veyon · debian · 13
Observed:
References
- [https://ftp.suse.com/pub/projects/security/csaf/suse-su-2019_0060-1.json]
- [https://osv.dev/vulnerability/DEBIAN-CVE-2018-20021]
- [https://security-tracker.debian.org/tracker/CVE-2018-20021]
[Debian Security Tracker] · [FIRST EPSS] · [OSV Package Vulnerability Database] · [SUSE security advisories and VEX]