Ubuntu USN · USN-8494-1

LibVNCServer vulnerability

Published: Thu, 02 Jul 2026 13:22

CVE-2026-50538

Summary

LibVNCServer could be made to crash or run programs if it received specially crafted network traffic.

Details

It was discovered that LibVNCServer incorrectly handled the Tight decoder in libvncclient. A remote attacker could use this issue to cause LibVNCServer to crash, resulting in a denial of service, or possibly execute arbitrary code.

Recommended actions per Ubuntu release

StackPatch playbook auto-generated per release codename and per affected package.

Ubuntu jammy

libvncserver→0.9.13+dfsg-3ubuntu0.2apt_upgrade
Standard apt upgrade. Install 0.9.13+dfsg-3ubuntu0.2 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y libvncserver
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
libvncclient1→0.9.13+dfsg-3ubuntu0.2apt_upgrade
Standard apt upgrade. Install 0.9.13+dfsg-3ubuntu0.2 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y libvncclient1
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
libvncserver-dev→0.9.13+dfsg-3ubuntu0.2apt_upgrade
Standard apt upgrade. Install 0.9.13+dfsg-3ubuntu0.2 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y libvncserver-dev
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
libvncserver1→0.9.13+dfsg-3ubuntu0.2apt_upgrade
Standard apt upgrade. Install 0.9.13+dfsg-3ubuntu0.2 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y libvncserver1
```
Most apt upgrades restart their service automatically. needrestart lists anything else.

Ubuntu noble

libvncserver→0.9.14+dfsg-1ubuntu0.2apt_upgrade
Standard apt upgrade. Install 0.9.14+dfsg-1ubuntu0.2 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y libvncserver
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
libvncclient1→0.9.14+dfsg-1ubuntu0.2apt_upgrade
Standard apt upgrade. Install 0.9.14+dfsg-1ubuntu0.2 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y libvncclient1
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
libvncserver-dev→0.9.14+dfsg-1ubuntu0.2apt_upgrade
Standard apt upgrade. Install 0.9.14+dfsg-1ubuntu0.2 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y libvncserver-dev
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
libvncserver1→0.9.14+dfsg-1ubuntu0.2apt_upgrade
Standard apt upgrade. Install 0.9.14+dfsg-1ubuntu0.2 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y libvncserver1
```
Most apt upgrades restart their service automatically. needrestart lists anything else.

Ubuntu questing

libvncserver→0.9.15+dfsg-1ubuntu0.2apt_upgrade
Standard apt upgrade. Install 0.9.15+dfsg-1ubuntu0.2 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y libvncserver
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
libvncclient1→0.9.15+dfsg-1ubuntu0.2apt_upgrade
Standard apt upgrade. Install 0.9.15+dfsg-1ubuntu0.2 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y libvncclient1
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
libvncserver-dev→0.9.15+dfsg-1ubuntu0.2apt_upgrade
Standard apt upgrade. Install 0.9.15+dfsg-1ubuntu0.2 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y libvncserver-dev
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
libvncserver1→0.9.15+dfsg-1ubuntu0.2apt_upgrade
Standard apt upgrade. Install 0.9.15+dfsg-1ubuntu0.2 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y libvncserver1
```
Most apt upgrades restart their service automatically. needrestart lists anything else.

Ubuntu resolute

libvncserver→0.9.15+dfsg-3ubuntu0.2apt_upgrade
Standard apt upgrade. Install 0.9.15+dfsg-3ubuntu0.2 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y libvncserver
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
libvncclient1→0.9.15+dfsg-3ubuntu0.2apt_upgrade
Standard apt upgrade. Install 0.9.15+dfsg-3ubuntu0.2 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y libvncclient1
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
libvncserver-dev→0.9.15+dfsg-3ubuntu0.2apt_upgrade
Standard apt upgrade. Install 0.9.15+dfsg-3ubuntu0.2 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y libvncserver-dev
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
libvncserver1→0.9.15+dfsg-3ubuntu0.2apt_upgrade
Standard apt upgrade. Install 0.9.15+dfsg-3ubuntu0.2 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y libvncserver1
```
Most apt upgrades restart their service automatically. needrestart lists anything else.

Are YOU affected by USN-8494-1?

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

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