Vulnerability · Published Nov 4, 2020 · Assigned by mitre
CVE-2020-28049
Medium 6.3
In plain English
A medium-severity race condition in the sddm package (Alpine). There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 36% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
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 packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine:v3.20 | sddm | 0.19.0-r0 | ALPINE-CVE-2020-28049 |
| Alpine:v3.21 | sddm | 0.19.0-r0 | ALPINE-CVE-2020-28049 |
| Alpine:v3.22 | sddm | 0.19.0-r0 | ALPINE-CVE-2020-28049 |
| Alpine:v3.23 | sddm | 0.19.0-r0 | ALPINE-CVE-2020-28049 |
| Alpine:v3.24 | sddm | 0.19.0-r0 | ALPINE-CVE-2020-28049 |
| Debian:12 | sddm | 0.19.0-1 | DEBIAN-CVE-2020-28049 |
| Debian:13 | sddm | 0.19.0-1 | DEBIAN-CVE-2020-28049 |
| Debian:14 | sddm | 0.19.0-1 | DEBIAN-CVE-2020-28049 |
Affected products (as reported)
Weakness: CWE-362 · Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N
References
- https://github.com/sddm/sddm/releases
- https://bugzilla.suse.com/show_bug.cgi?id=CVE-2020-28049
- https://github.com/sddm/sddm/blob/v0.19.0/ChangeLog
- DSA-4783 vendor-advisory
- [debian-lts-announce] 20201106 [SECURITY] [DLA 2436-1] sddm security update mailing-list
- openSUSE-SU-2020:1870 vendor-advisory
- FEDORA-2021-7066b95c99 vendor-advisory
- GLSA-202402-02 vendor-advisory