7.8
CVE-2021-28701
- EPSS 0.06%
- Published 08.09.2021 14:15:08
- Last modified 21.11.2024 06:00:10
- Source security@xen.org
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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.
Data is provided by the National Vulnerability Database (NVD)
Debian ≫ Debian Linux Version11.0
Fedoraproject ≫ Fedora Version33
Fedoraproject ≫ Fedora Version34
Fedoraproject ≫ Fedora Version35
Zu dieser CVE wurde keine CISA KEV oder CERT.AT-Warnung gefunden.
| Type | Source | Score | Percentile |
|---|---|---|---|
| EPSS | FIRST.org | 0.06% | 0.186 |
| Source | 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.