CVE-2021-28703
Xen Grant Table V2 Status Page Memory Access Control Vulnerability (Double Access)
Description
grant table v2 status pages may remain accessible after de-allocation (take two) Guest get 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, get de-allocated when a guest switched (back) from v2 to v1. The freeing of such pages requires that the hypervisor know where in the guest these pages were mapped. The hypervisor tracks only one use within guest space, but racing requests from the guest to insert mappings of these pages may result in any of them to become mapped in multiple locations. Upon switching back from v2 to v1, the guest would then retain access to a page that was freed and perhaps re-used for other purposes. This bug was fortuitously fixed by code cleanup in Xen 4.14, and backported to security-supported Xen branches as a prerequisite of the fix for XSA-378.
INFO
Published Date :
Dec. 7, 2021, 12:15 p.m.
Last Modified :
Nov. 21, 2024, 6 a.m.
Source :
[email protected]
Remotely Exploitable :
No
Impact Score :
5.9
Exploitability Score :
1.0
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2021-28703.
| URL | Resource |
|---|---|
| https://security.gentoo.org/glsa/202402-07 | |
| https://xenbits.xenproject.org/xsa/advisory-387.txt | Vendor Advisory |
| https://security.gentoo.org/glsa/202402-07 | |
| https://xenbits.xenproject.org/xsa/advisory-387.txt | Vendor Advisory |
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2021-28703 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2021-28703 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by af854a3a-2127-422b-91ae-364da2661108
Nov. 21, 2024
Action Type Old Value New Value Added Reference https://security.gentoo.org/glsa/202402-07 Added Reference https://xenbits.xenproject.org/xsa/advisory-387.txt -
CVE Modified by [email protected]
May. 14, 2024
Action Type Old Value New Value -
CVE Modified by [email protected]
Feb. 04, 2024
Action Type Old Value New Value Added Reference Xen Project https://security.gentoo.org/glsa/202402-07 [No types assigned] -
Initial Analysis by [email protected]
Dec. 09, 2021
Action Type Old Value New Value Added CVSS V2 NIST (AV:L/AC:M/Au:N/C:C/I:C/A:C) Added CVSS V3.1 NIST AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H Changed Reference Type https://xenbits.xenproject.org/xsa/advisory-387.txt No Types Assigned https://xenbits.xenproject.org/xsa/advisory-387.txt Vendor Advisory Added CWE NIST NVD-CWE-Other Added CPE Configuration OR *cpe:2.3:o:xen:xen:*:*:*:*:*:*:x86:* versions up to (excluding) 14.4
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2021-28703 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2021-28703
weaknesses.
Exploit Prediction
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.
0.11 }} 0.01%
score
0.30707
percentile