How severe is CVE-2020-25697?

CVE-2020-25697 has a CVSS 3.x base score of 7.0, rated high 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 high.

Is CVE-2020-25697 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (25th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-25697?

CVE-2020-25697 affects X.org X Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-25697?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2020-25697 published?

CVE-2020-25697 was published on 2021-05-26 and last updated on 2026-06-17.

CVE-2020-25697

CVE-2020-25697 is a high-severity vulnerability in X.org X Server with a CVSS 3.x base score of 7.0. 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-306.

Key facts

Severity: High (CVSS 3.x base score 7.0)
CVSS v2: 4.4
EPSS exploit prediction: 0% (25th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-306
Affected product: X.org X Server
Published: 2021-05-26
Last modified: 2026-06-17

Description

A privilege escalation flaw was found in the Xorg-x11-server due to a lack of authentication for X11 clients. This flaw allows an attacker to take control of an X application by impersonating the server it is expecting to connect to.

Frequently asked questions

What is CVE-2020-25697?: A privilege escalation flaw was found in the Xorg-x11-server due to a lack of authentication for X11 clients. This flaw allows an attacker to take control of an X application by impersonating the server it is expecting to connect to.
How severe is CVE-2020-25697?: CVE-2020-25697 has a CVSS 3.x base score of 7.0, rated high 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 high.
Is CVE-2020-25697 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (25th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-25697?: CVE-2020-25697 affects X.org X Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-25697?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2020-25697 published?: CVE-2020-25697 was published on 2021-05-26 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:x.org:x_server:-:*:*:*:*:*:*:*

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