CVE-2020-28049: Race Condition

Published Nov 4, 2020
·
Updated

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.

Affected Software

8 affected componentsFixes available
debian/sddm
0.18.0-1+deb10u10.19.0-30.19.0-50.20.0-1
debian/sddm<=0.18.1-1, <=0.18.0-1
0.19.0-10.18.0-1+deb10u1
Sddm Project Sddm<0.19.0
openSUSE Leap=15.1
openSUSE Leap=15.2
Debian Debian Linux=9.0
Debian Debian Linux=10.0
Fedoraproject Fedora=33

Event History

Nov 4, 2020
CVE Published
via MITRE·12:00 AM
Data Sourced
via MITRE·12:00 AM
Description
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Frequently Asked Questions

1

What is CVE-2020-28049?

CVE-2020-28049 is a vulnerability discovered in SDDM before version 0.19.0 that incorrectly starts the X server in a way that allows local unprivileged users to access X server display contents without proper authentication.

2

What is the severity of CVE-2020-28049?

CVE-2020-28049 has a severity value of 6.3, which is considered medium.

3

How does CVE-2020-28049 affect SDDM?

CVE-2020-28049 affects SDDM versions before 0.19.0 by allowing local unprivileged users to create a connection to the X server without proper authentication.

4

How can I fix CVE-2020-28049?

To fix CVE-2020-28049, it is recommended to update SDDM to version 0.19.0 or higher.

5

Where can I find more information about CVE-2020-28049?

More information about CVE-2020-28049 can be found in the references provided: [1] [2] [3].

Contact

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