Citrix Releases Security Updates for Hypervisor

Security updates address multiple vulnerabilities affecting Citrix Hypervisor

Threat ID:: CC-4121
Threat Severity:: Information only
Published:: 28 June 2022 10:38 AM

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Summary

Security updates address multiple vulnerabilities affecting Citrix Hypervisor

Affected platforms

The following platforms are known to be affected:

Versions: all prior to 8.2 Cumulative Update 1

Citrix Hypervisor

Versions: all prior to 7.1 Cumulative update 2

Citrix XenServer

Threat details

Introduction

Citrix has released security updates to address multiple vulnerabilities affecting Citrix Hypervisor. An attacker could exploit one of these vulnerabilities to take control of an affected system.

Remediation advice

Affected organisations are encouraged to review Citrix Security Update CTX460064 and apply the relevant updates.

Remediation steps

Type	Step
Patch	Citrix Hypervisor 8.2 CU1 LTSR \| CTX459954 https://support.citrix.com/article/CTX459954
Patch	Citrix XenServer 7.1 CU2 LTSR \| CTX459953 https://support.citrix.com/article/CTX459953

Definitive source of threat updates

CVE Vulnerabilities

Status Published

CVE-2022-26362

x86 pv: Race condition in typeref acquisition Xen maintains a type reference count for pages, in addition to a regular reference count. This scheme is used to maintain invariants required for Xen's safety, e.g. PV guests may not have direct writeable access to pagetables; updates need auditing by Xen. Unfortunately, the logic for acquiring a type reference has a race condition, whereby a safely TLB flush is issued too early and creates a window where the guest can re-establish the read/write mapping before writeability is prohibited.

Status Published

CVE-2022-21123

Incomplete cleanup of multi-core shared buffers for some Intel(R) Processors may allow an authenticated user to potentially enable information disclosure via local access.

Status Published

CVE-2022-21125

Incomplete cleanup of microarchitectural fill buffers on some Intel(R) Processors may allow an authenticated user to potentially enable information disclosure via local access.

Status Published

CVE-2022-21127

Incomplete cleanup in specific special register read operations for some Intel(R) Processors may allow an authenticated user to potentially enable information disclosure via local access.

Status Published

CVE-2022-21166

Incomplete cleanup in specific special register write operations for some Intel(R) Processors may allow an authenticated user to potentially enable information disclosure via local access.

Last edited: 28 June 2022 10:38 am