How severe is CVE-2000-0453?

CVE-2000-0453 has a CVSS 2.0 base score of 5.0, rated medium severity.

Is CVE-2000-0453 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2000-0453?

CVE-2000-0453 primarily affects Xfree86 Project X11r6. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2000-0453?

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

When was CVE-2000-0453 published?

CVE-2000-0453 was published on 2000-05-18 and last updated on 2026-06-16.

CVE-2000-0453

CVE-2000-0453 is a medium-severity vulnerability in Xfree86 Project X11r6 with a CVSS 2.0 base score of 5.0. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Medium (CVSS 2.0 base score 5.0)
EPSS exploit prediction: 3% (86th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Xfree86 Project X11r6
Published: 2000-05-18
Last modified: 2026-06-16

Description

XFree86 3.3.x and 4.0 allows a user to cause a denial of service via a negative counter value in a malformed TCP packet that is sent to port 6000.

Frequently asked questions

What is CVE-2000-0453?: XFree86 3.3.x and 4.0 allows a user to cause a denial of service via a negative counter value in a malformed TCP packet that is sent to port 6000.
How severe is CVE-2000-0453?: CVE-2000-0453 has a CVSS 2.0 base score of 5.0, rated medium severity.
Is CVE-2000-0453 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2000-0453?: CVE-2000-0453 primarily affects Xfree86 Project X11r6. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2000-0453?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2000-0453 published?: CVE-2000-0453 was published on 2000-05-18 and last updated on 2026-06-16.

References

Affected products (3)

cpe:2.3:a:xfree86_project:x11r6:3.3.5:*:*:*:*:*:*:*
cpe:2.3:a:xfree86_project:x11r6:3.3.6:*:*:*:*:*:*:*
cpe:2.3:a:xfree86_project:x11r6:4.0:*:*:*:*:*:*:*

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