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CVE-2021-28701 Detail

Description

Another race in XENMAPSPACE_grant_table handling Guests are permitted access to certain Xen-owned pages of memory. The majority of such pages remain allocated / associated with a guest for its entire lifetime. Grant table v2 status pages, however, are de-allocated when a guest switches (back) from v2 to v1. Freeing such pages requires that the hypervisor enforce that no parallel request can result in the addition of a mapping of such a page to a guest. That enforcement was missing, allowing guests to retain access to pages that were freed and perhaps re-used for other purposes. Unfortunately, when XSA-379 was being prepared, this similar issue was not noticed.


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/2021/09/08/2 Mailing List  Third Party Advisory 
http://xenbits.xen.org/xsa/advisory-384.html Vendor Advisory 
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/3HEHUIUWSSMCQGQY3GWX4J2SZGYP5W2Z/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CEHZLIR5DFYYQBH55AERWHLO54OFU42C/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/L4MI3MQAPGILCLXBGQWPZHGE3ALSO4ZU/
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-384.txt Vendor Advisory 

Weakness Enumeration

CWE-ID CWE Name Source
CWE-362 Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition') cwe source acceptance level NIST  

Known Affected Software Configurations Switch to CPE 2.2

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Change History

12 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2021-28701
NVD Published Date:
09/08/2021
NVD Last Modified:
11/06/2023
Source:
Xen Project