CVE-2021-28701
published 2021-09-08CVE-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…
PriorityP339high7.8CVSS 3.1
AVLACHPRLUINSCCHIHAH
EPSS
0.27%
18.1th percentile
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.
Affected
13 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | debian_linux | — | — |
| debian | xen | < xen 4.14.3-1 (bookworm) | xen 4.14.3-1 (bookworm) |
| fedoraproject | fedora | — | — |
| fedoraproject | fedora | — | — |
| fedoraproject | fedora | — | — |
| xen | xen | — | — |
| xen | xen | >= 0 < 4.14.3-1~deb11u1 | 4.14.3-1~deb11u1 |
| xen | xen | >= 0 < 4.14.3-1 | 4.14.3-1 |
| xen | xen | >= 0 < 4.14.3-1 | 4.14.3-1 |
| xen | xen | >= 0 < 4.14.3-1 | 4.14.3-1 |
| xen | xen | >= 4.0.0 | — |
| xen | xen | >= 4.12.x < unspecified | unspecified |
| xen | xen | >= 4.15.x < unspecified | unspecified |
CVSS provenance
nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
nvdv2.04.4MEDIUMAV:L/AC:M/Au:N/C:P/I:P/A:P
osv7.8HIGH
vendor_debian7.8HIGH
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GHSA
GHSA-423x-f92f-r5fm: Another race in XENMAPSPACE_grant_table handling Guests are permitted access to certain Xen-owned pages of memory
ghsa_unreviewed·2022-05-24
CVE-2021-28701 [HIGH] CWE-269 GHSA-423x-f92f-r5fm: Another race in XENMAPSPACE_grant_table handling Guests are permitted access to certain Xen-owned pages of memory
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.
OSV
CVE-2021-28701: Another race in XENMAPSPACE_grant_table handling Guests are permitted access to certain Xen-owned pages of memory
osv·2021-09-08·CVSS 7.8
CVE-2021-28701 [HIGH] CVE-2021-28701: Another race in XENMAPSPACE_grant_table handling Guests are permitted access to certain Xen-owned pages of memory
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.
Debian
CVE-2021-28701: xen - Another race in XENMAPSPACE_grant_table handling Guests are permitted access to ...
vendor_debian·2021·CVSS 7.8
CVE-2021-28701 [HIGH] CVE-2021-28701: xen - Another race in XENMAPSPACE_grant_table handling Guests are permitted access to ...
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.
Scope: local
bookworm: resolved (fixed in 4.14.3-1)
bullseye: resolved (fixed in 4.14.3-1~deb11u1)
forky: resolved (fixed in 4.14.3
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
http://www.openwall.com/lists/oss-security/2021/09/08/2http://xenbits.xen.org/xsa/advisory-384.htmlhttps://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/202208-23https://www.debian.org/security/2021/dsa-4977https://xenbits.xenproject.org/xsa/advisory-384.txthttp://www.openwall.com/lists/oss-security/2021/09/08/2http://xenbits.xen.org/xsa/advisory-384.htmlhttps://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/202208-23https://www.debian.org/security/2021/dsa-4977https://xenbits.xenproject.org/xsa/advisory-384.txt
2021-09-08
Published