Bug 1970530 (CVE-2021-0086, CVE-2021-0089, CVE-2021-26313, CVE-2021-26314)

Summary:	CVE-2021-0089 CVE-2021-26313 CVE-2021-0086 CVE-2021-26314 xen: speculative code store bypass (XSA-375)
Product:	[Other] Security Response	Reporter:	Guilherme de Almeida Suckevicz <gsuckevi>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED UPSTREAM	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	jforbes, m.a.young
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
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Fixed In Version:		Doc Type:	If docs needed, set a value
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Clone Of:		Environment:
Last Closed:	2021-06-10 21:04:01 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
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oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	1970531
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Description Guilherme de Almeida Suckevicz 2021-06-10 16:22:27 UTC

Modern superscalar processors may employ sophisticated decoding and caching of the instruction stream to improve performance.  However, a consequence is that self-modifying code updates may not take effect instantly. Whatever the architectural guarantees, some CPUs have microarchitectural behaviour whereby the stale instruction stream may be speculatively decoded and executed. Speculation of this form can suffer from type confusion in registers, and potentially leak data.

Reference:
http://xenbits.xen.org/xsa/advisory-375.html

Comment 1 Guilherme de Almeida Suckevicz 2021-06-10 16:22:45 UTC

Created xen tracking bugs for this issue:

Affects: fedora-all [bug 1970531]

Comment 2 Product Security DevOps Team 2021-06-10 21:04:01 UTC

This CVE Bugzilla entry is for community support informational purposes only as it does not affect a package in a commercially supported Red Hat product. Refer to the dependent bugs for status of those individual community products.