CVE-2018-20021 · cross-distro fix matrix

CVE-2018-20021: 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

Affects 3 Linux releases across 12 (distro × package) combinations.

Fix per ecosystem

Each block below is a distro release where CVE-2018-20021 has a known fix. Run the listed command on that distro to remediate.

Debian bullseye

Source: Debian Security Tracker

libvncserver→ fixed in0.9.11+dfsg-1.2urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y libvncserver
```
ssvnc→ fixed in1.0.29-5urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y ssvnc
```
tightvnc→ fixed in1:1.3.9-9.1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y tightvnc
```
veyon→ fixed in4.1.4+repack1-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y veyon
```

Debian bookworm

Source: Debian Security Tracker

libvncserver→ fixed in0.9.11+dfsg-1.2urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y libvncserver
```
ssvnc→ fixed in1.0.29-5urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y ssvnc
```
tightvnc→ fixed in1:1.3.9-9.1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y tightvnc
```
veyon→ fixed in4.1.4+repack1-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y veyon
```

Debian trixie

Source: Debian Security Tracker

libvncserver→ fixed in0.9.11+dfsg-1.2urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y libvncserver
```
ssvnc→ fixed in1.0.29-5urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y ssvnc
```
tightvnc→ fixed in1:1.3.9-9.1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y tightvnc
```
veyon→ fixed in4.1.4+repack1-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y veyon
```

Are YOU affected by CVE-2018-20021?

5-second check on your actual server. Reads /etc/os-release, uname -r, and the distro's package manager; matches against this same cross-source index live.

curl https://mindsparkstack.com/scan.sh | bash

Form-based quickscan View on NVD

Continuous monitoring beats manual checking

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