How severe is CVE-2016-9383?

CVE-2016-9383 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-2016-9383 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (39th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2016-9383?

CVE-2016-9383 primarily affects Citrix Xenserver. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2016-9383?

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-2016-9383 published?

CVE-2016-9383 was published on 2017-01-23 and last updated on 2026-06-17.

CVE-2016-9383

CVE-2016-9383 is a high-severity vulnerability in Citrix Xenserver 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-20.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 7.2
EPSS exploit prediction: 1% (39th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Citrix Xenserver
Published: 2017-01-23
Last modified: 2026-06-17

Description

Xen, when running on a 64-bit hypervisor, allows local x86 guest OS users to modify arbitrary memory and consequently obtain sensitive information, cause a denial of service (host crash), or execute arbitrary code on the host by leveraging broken emulation of bit test instructions.

Frequently asked questions

What is CVE-2016-9383?: Xen, when running on a 64-bit hypervisor, allows local x86 guest OS users to modify arbitrary memory and consequently obtain sensitive information, cause a denial of service (host crash), or execute arbitrary code on the host by leveraging broken emulation of bit test instructions.
How severe is CVE-2016-9383?: CVE-2016-9383 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-2016-9383 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (39th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-9383?: CVE-2016-9383 primarily affects Citrix Xenserver. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2016-9383?: 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-2016-9383 published?: CVE-2016-9383 was published on 2017-01-23 and last updated on 2026-06-17.

References

Affected products (5)

cpe:2.3:o:xen:xen:*:*:*:*:*:*:*:*
cpe:2.3:a:citrix:xenserver:6.0.2:*:*:*:*:*:*:*
cpe:2.3:a:citrix:xenserver:6.2.0:*:*:*:*:*:*:*
cpe:2.3:a:citrix:xenserver:6.5:*:*:*:*:*:*:*
cpe:2.3:a:citrix:xenserver:7.0:*:*:*:*:*:*:*

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