How severe is CVE-2018-18883?

CVE-2018-18883 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2018-18883 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (35th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-18883?

CVE-2018-18883 affects Xen. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-18883?

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-2018-18883 published?

CVE-2018-18883 was published on 2018-11-01 and last updated on 2026-06-17.

CVE-2018-18883

CVE-2018-18883 is a high-severity vulnerability in Xen with a CVSS 3.x base score of 8.8. 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-476.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 7.2
EPSS exploit prediction: 0% (35th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-476
Affected product: Xen
Published: 2018-11-01
Last modified: 2026-06-17

Description

An issue was discovered in Xen 4.9.x through 4.11.x, on Intel x86 platforms, allowing x86 HVM and PVH guests to cause a host OS denial of service (NULL pointer dereference) or possibly have unspecified other impact because nested VT-x is not properly restricted.

Frequently asked questions

What is CVE-2018-18883?: An issue was discovered in Xen 4.9.x through 4.11.x, on Intel x86 platforms, allowing x86 HVM and PVH guests to cause a host OS denial of service (NULL pointer dereference) or possibly have unspecified other impact because nested VT-x is not properly restricted.
How severe is CVE-2018-18883?: CVE-2018-18883 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2018-18883 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (35th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-18883?: CVE-2018-18883 affects Xen. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-18883?: 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-2018-18883 published?: CVE-2018-18883 was published on 2018-11-01 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:xen:xen:*:*:*:*:*:*:*:*

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