How severe is CVE-2016-9380?

CVE-2016-9380 has a CVSS 3.x base score of 7.5, 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 none.

Is CVE-2016-9380 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (34th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2016-9380?

CVE-2016-9380 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-2016-9380?

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-2016-9380 published?

CVE-2016-9380 was published on 2017-01-23 and last updated on 2026-06-17.

CVE-2016-9380

CVE-2016-9380 is a high-severity vulnerability in Citrix Xenserver with a CVSS 3.x base score of 7.5. 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: High (CVSS 3.x base score 7.5)
CVSS v2: 4.6
EPSS exploit prediction: 0% (34th 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

The pygrub boot loader emulator in Xen, when nul-delimited output format is requested, allows local pygrub-using guest OS administrators to read or delete arbitrary files on the host via NUL bytes in the bootloader configuration file.

Frequently asked questions

What is CVE-2016-9380?: The pygrub boot loader emulator in Xen, when nul-delimited output format is requested, allows local pygrub-using guest OS administrators to read or delete arbitrary files on the host via NUL bytes in the bootloader configuration file.
How severe is CVE-2016-9380?: CVE-2016-9380 has a CVSS 3.x base score of 7.5, 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 none.
Is CVE-2016-9380 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (34th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-9380?: CVE-2016-9380 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-2016-9380?: 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-2016-9380 published?: CVE-2016-9380 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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