USN-9089-1: x11vnc vulnerability

Q: Who can exploit this issue?

A local attacker could exploit the insecure permissions on shared memory segments created by x11vnc. The provided information does not indicate that remote access alone is sufficient.

Q: What could an attacker gain or do?

An attacker may be able to obtain sensitive information from x11vnc shared memory or modify screen contents.

Published Nov 12, 2026

Updated

It was discovered that x11vnc created shared memory segments with insecure permissions. A local attacker could possibly use this issue to obtain sensitive information or modify screen contents.

Affected Software

2 affected componentsFixes available

All of the following

ubuntu/x11vnc<Ubuntu Pro

Ubuntu Pro

Ubuntu Ubuntu=20.04

Remediation

Recommended actions to resolve this vulnerability, in priority order.

Upgrade
Upgrade ubuntu/x11vnc to a version that resolves this vulnerability.
Fixed in Ubuntu Pro

Event History

Nov 12, 2026

Advisory Published

via Ubuntu·12:00 AM

Data Sourced

via Ubuntu·12:00 AM

DescriptionAffected Software

Child vulnerabilities

Contains the following vulnerabilities.

CVE-2020-29074

Frequently Asked Questions

Who can exploit this issue?

A local attacker could exploit the insecure permissions on shared memory segments created by x11vnc. The provided information does not indicate that remote access alone is sufficient.

What could an attacker gain or do?