CVE-2016-6258
CVE-2016-6258 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-284.
Key facts
- Severity: High (CVSS 3.x base score 8.8)
- CVSS v2: 7.2
- EPSS exploit prediction: 0% (32nd percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-284
- Affected product: Citrix Xenserver
- Published:
- Last modified:
Description
The PV pagetable code in arch/x86/mm.c in Xen 4.7.x and earlier allows local 32-bit PV guest OS administrators to gain host OS privileges by leveraging fast-paths for updating pagetable entries.
Frequently asked questions
- What is CVE-2016-6258?
- The PV pagetable code in arch/x86/mm.c in Xen 4.7.x and earlier allows local 32-bit PV guest OS administrators to gain host OS privileges by leveraging fast-paths for updating pagetable entries.
- How severe is CVE-2016-6258?
- CVE-2016-6258 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-2016-6258 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (32nd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2016-6258?
- CVE-2016-6258 primarily affects Citrix Xenserver. In total, 33 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2016-6258?
- 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-2016-6258 published?
- CVE-2016-6258 was published on 2016-08-02 and last updated on 2026-06-17.
References
- http://support.citrix.com/article/CTX214954
- http://www.debian.org/security/2016/dsa-3633
- http://www.oracle.com/technetwork/topics/security/ovmbulletinjul2016-3090546.html
- http://www.securityfocus.com/bid/92131
- http://www.securitytracker.com/id/1036446
- http://xenbits.xen.org/xsa/advisory-182.html
- http://xenbits.xen.org/xsa/xsa182-4.5.patch
- http://xenbits.xen.org/xsa/xsa182-4.6.patch
- http://xenbits.xen.org/xsa/xsa182-unstable.patch
- https://security.gentoo.org/glsa/201611-09
Affected products (33)
- cpe:2.3:o:xen:xen:3.4.0:*:*:*:*:*:*:*
- 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:*:*:*:*:*:*:*
- cpe:2.3:o:xen:xen:4.0.1:*:*:*:*:*:*:*
- cpe:2.3:o:xen:xen:4.0.3:*:*:*:*:*:*:*
- cpe:2.3:o:xen:xen:4.0.4:*:*:*:*:*:*:*
- cpe:2.3:o:xen:xen:4.1.0:*:*:*:*:*:*:*
- cpe:2.3:o:xen:xen:4.1.1:*:*:*:*:*:*:*
- cpe:2.3:o:xen:xen:4.1.2:*:*:*:*:*:*:*
- cpe:2.3:o:xen:xen:4.1.3:*:*:*:*:*:*:*
- cpe:2.3:o:xen:xen:4.1.4:*:*:*:*:*:*:*
- cpe:2.3:o:xen:xen:4.1.5:*:*:*:*:*:*:*
- cpe:2.3:o:xen:xen:4.2.0:*:*:*:*:*:*:*
- cpe:2.3:o:xen:xen:4.2.1:*:*:*:*:*:*:*
- cpe:2.3:o:xen:xen:4.2.2:*:*:*:*:*:*:*
- cpe:2.3:o:xen:xen:4.2.3:*:*:*:*:*:*:*
- cpe:2.3:o:xen:xen:4.3.0:*:*:*:*:*:*:*
- cpe:2.3:o:xen:xen:4.3.1:*:*:*:*:*:*:*
- cpe:2.3:o:xen:xen:4.4.0:*:*:*:*:*:*:*
- cpe:2.3:o:xen:xen:4.4.1:*:*:*:*:*:*:*
- cpe:2.3:o:xen:xen:4.5.0:*:*:*:*:*:*:*
- cpe:2.3:o:xen:xen:4.6.0:*:*:*:*:*:*:*
- cpe:2.3:o:xen:xen:4.6.1:*:*:*:*:*:*:*
- cpe:2.3:o:xen:xen:4.6.3:*:*:*:*:*:*:*
- cpe:2.3:o:xen:xen:4.7.0:*:*:*:*:*:*:*
- cpe:2.3:a:citrix:xenserver:6.0:*:*:*:*:*:*:*
- cpe:2.3:a:citrix:xenserver:6.0.2:*:*:*:*:*:*:*
- cpe:2.3:a:citrix:xenserver:6.1:*:*:*:*:*:*:*
- cpe:2.3:a:citrix:xenserver:6.2.0:sp1:*:*:*:*:*:*
- cpe:2.3:a:citrix:xenserver:6.5.0:sp1:*:*:*:*:*:*
- cpe:2.3:a:citrix:xenserver:7.0:*:*:*:*:*:*:*
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