How severe is CVE-2011-1166?

CVE-2011-1166 has a CVSS 2.0 base score of 5.5, rated medium severity.

Is CVE-2011-1166 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (48th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2011-1166?

CVE-2011-1166 primarily affects Xen. In total, 19 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2011-1166?

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

When was CVE-2011-1166 published?

CVE-2011-1166 was published on 2014-01-07 and last updated on 2026-06-16.

CVE-2011-1166

CVE-2011-1166 is a medium-severity vulnerability in Xen with a CVSS 2.0 base score of 5.5. 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-20.

Key facts

Severity: Medium (CVSS 2.0 base score 5.5)
EPSS exploit prediction: 1% (48th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Xen
Published: 2014-01-07
Last modified: 2026-06-16

Description

Xen, possibly before 4.0.2, allows local 64-bit PV guests to cause a denial of service (host crash) by specifying user mode execution without user-mode pagetables.

Frequently asked questions

What is CVE-2011-1166?: Xen, possibly before 4.0.2, allows local 64-bit PV guests to cause a denial of service (host crash) by specifying user mode execution without user-mode pagetables.
How severe is CVE-2011-1166?: CVE-2011-1166 has a CVSS 2.0 base score of 5.5, rated medium severity.
Is CVE-2011-1166 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (48th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2011-1166?: CVE-2011-1166 primarily affects Xen. In total, 19 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2011-1166?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2011-1166 published?: CVE-2011-1166 was published on 2014-01-07 and last updated on 2026-06-16.

References

Affected products (19)

cpe:2.3:o:xen:xen:*:*:*:*:*:*:*:*
cpe:2.3:o:xen:xen:3.0.2:*:*:*:*:*:*:*
cpe:2.3:o:xen:xen:3.0.3:*:*:*:*:*:*:*
cpe:2.3:o:xen:xen:3.0.4:*:*:*:*:*:*:*
cpe:2.3:o:xen:xen:3.1.3:*:*:*:*:*:*:*
cpe:2.3:o:xen:xen:3.1.4:*:*:*:*:*:*:*
cpe:2.3:o:xen:xen:3.2.0:*:*:*:*:*:*:*
cpe:2.3:o:xen:xen:3.2.1:*:*:*:*:*:*:*
cpe:2.3:o:xen:xen:3.2.2:*:*:*:*:*:*:*
cpe:2.3:o:xen:xen:3.2.3:*:*:*:*:*:*:*
cpe:2.3:o:xen:xen:3.3.0:*:*:*:*:*:*:*
cpe:2.3:o:xen:xen:3.3.1:*:*:*:*:*:*:*
cpe:2.3:o:xen:xen:3.3.2:*:*:*:*:*:*:*
cpe:2.3:o:xen:xen:3.4.0:*:*:*:*:*:*:*
cpe:2.3:o:xen:xen:3.4.1:*:*:*:*:*:*:*
cpe:2.3:o:xen:xen:3.4.2:*:*:*:*:*:*:*
cpe:2.3:o:xen:xen:3.4.3:*:*:*:*:*:*:*
cpe:2.3:o:xen:xen:3.4.4:*:*:*:*:*:*:*
cpe:2.3:o:xen:xen:4.0.0:*:*:*:*:*:*:*

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