How severe is CVE-2020-28049?

CVE-2020-28049 has a CVSS 3.x base score of 6.3, rated medium severity. It is exploitable over local access with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2020-28049 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (33rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-28049?

CVE-2020-28049 primarily affects Sddm Project Sddm. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-28049?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2020-28049 published?

CVE-2020-28049 was published on 2020-11-04 and last updated on 2026-06-17.

CVE-2020-28049

CVE-2020-28049 is a medium-severity vulnerability in Sddm Project Sddm with a CVSS 3.x base score of 6.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-362.

Key facts

Severity: Medium (CVSS 3.x base score 6.3)
CVSS v2: 3.3
EPSS exploit prediction: 0% (33rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-362
Affected product: Sddm Project Sddm
Published: 2020-11-04
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2020-28049?: 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.
How severe is CVE-2020-28049?: CVE-2020-28049 has a CVSS 3.x base score of 6.3, rated medium severity. It is exploitable over local access with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2020-28049 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (33rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-28049?: CVE-2020-28049 primarily affects Sddm Project Sddm. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-28049?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-28049 published?: CVE-2020-28049 was published on 2020-11-04 and last updated on 2026-06-17.

References

Affected products (6)

cpe:2.3:a:sddm_project:sddm:*:*:*:*:*:*:*:*
cpe:2.3:o:opensuse:leap:15.1:*:*:*:*:*:*:*
cpe:2.3:o:opensuse:leap:15.2:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*

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Other CWE-362 (Race Condition) vulnerabilities

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