7.8

CVE-2021-28701

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.
Daten sind bereitgestellt durch National Vulnerability Database (NVD)
Xen ≫ Xen Version >= 4.0.0
Debian ≫ Debian Linux Version11.0
Fedoraproject ≫ Fedora Version33
Fedoraproject ≫ Fedora Version34
Fedoraproject ≫ Fedora Version35
Zu dieser CVE wurde keine Warnung gefunden.
EPSS Metriken
Typ Quelle Score Percentile
EPSS FIRST.org 0.27% 0.18
CVSS Metriken
Quelle Base Score Exploit Score Impact Score Vector String
nvd@nist.gov 7.8 1.1 6
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
nvd@nist.gov 4.4 3.4 6.4
AV:L/AC:M/Au:N/C:P/I:P/A:P
CWE-362 Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.

https://security.gentoo.org/glsa/202208-23
Third Party Advisory
https://www.debian.org/security/2021/dsa-4977
Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/09/08/2
Third Party Advisory
Mailing List
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://xenbits.xenproject.org/xsa/advisory-384.txt
Vendor Advisory