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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities
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CVE-2021-28695 Detail

Description

IOMMU page mapping issues on x86 T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] Both AMD and Intel allow ACPI tables to specify regions of memory which should be left untranslated, which typically means these addresses should pass the translation phase unaltered. While these are typically device specific ACPI properties, they can also be specified to apply to a range of devices, or even all devices. On all systems with such regions Xen failed to prevent guests from undoing/replacing such mappings (CVE-2021-28694). On AMD systems, where a discontinuous range is specified by firmware, the supposedly-excluded middle range will also be identity-mapped (CVE-2021-28695). Further, on AMD systems, upon de-assigment of a physical device from a guest, the identity mappings would be left in place, allowing a guest continued access to ranges of memory which it shouldn't have access to anymore (CVE-2021-28696).


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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Hyperlink Resource
http://www.openwall.com/lists/oss-security/2021/09/01/1 Mailing List  Third Party Advisory 
http://www.openwall.com/lists/oss-security/2021/09/01/5 Mailing List  Third Party Advisory 
http://www.openwall.com/lists/oss-security/2021/09/01/6 Mailing List  Third Party Advisory 
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2VQCFAPBNGBBAOMJZG6QBREOG5IIDZID/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FZCNPSRPGFCQRYE2BI4D4Q4SCE56ANV2/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LPRVHW4J4ZCPPOHZEWP5MOJT7XDGFFPJ/
https://security.gentoo.org/glsa/202208-23 Third Party Advisory 
https://www.debian.org/security/2021/dsa-4977 Third Party Advisory 
https://xenbits.xenproject.org/xsa/advisory-378.txt Vendor Advisory 

Weakness Enumeration

CWE-ID CWE Name Source
NVD-CWE-noinfo Insufficient Information cwe source acceptance level NIST  

Known Affected Software Configurations Switch to CPE 2.2

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Change History

13 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2021-28695
NVD Published Date:
08/27/2021
NVD Last Modified:
11/06/2023
Source:
Xen Project