SB2020110548 - Race condition in sddm (Alpine package)



SB2020110548 - Race condition in sddm (Alpine package)

Published: November 5, 2020

Security Bulletin ID SB2020110548
Severity
Low
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Local access
Highest impact Data manipulation

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 security vulnerability.


1) Race condition (CVE-ID: CVE-2020-28049)

The vulnerability allows a local authenticated user to read and manipulate data.

An issue was discovered in SDDM before 0.19.0. It incorrectly starts the X server in a way that - for a short time period - allows local unprivileged users to create a connection to the X server without providing proper authentication. A local attacker can thus access X server display contents and, for example, intercept keystrokes or access the clipboard. This is caused by a race condition during Xauthority file creation.


Remediation

Install update from vendor's website.