CVE-2021-28708 is a high-severity vulnerability affecting Xen and Xen-based distributions like Debian and Fedora. It arises from improper handling of XENMEM_decrease_reservation operations in populate-on-demand (PoD) mode for x86 HVM and PVH guests, specifically when the specified page order is not 4k, 2M, or 1G. This flaw can lead to a host crash, indicating a denial-of-service risk. With a CVSS score of 8.8 (HIGH), this vulnerability has a local attack vector, low attack complexity, and requires low privileges, but can result in high impact to confidentiality, integrity, and availability (C:H/I:H/A:H). The EPSS score is very low at 0.00086, suggesting a low probability of exploitation in the wild. Currently, there is no known active exploitation, public exploit code (Metasploit, Nuclei, ExploitDB), or significant community discussion or media coverage surrounding this CVE. It is not listed in CISA's KEV catalog, further indicating a lack of widespread exploitation.
| Vendor | Product | Version(s) | CPE |
|---|---|---|---|
>= 4.7.0, <= 4.15.1CPE matchmatch criteria | cpe:2.3:o:xen:xen:*:*:*:*:*:*:x86:* | ||
11.0CPE matchmatch criteria | cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:* | ||
34CPE matchmatch criteria | cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:* | ||
35CPE matchmatch criteria | cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:* |
CVSS version used by this source: 3.1
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
The average CVE in this peer group has 0.0 Twitter, 0.1 Reddit, 0.2 Bluesky, 0.1 Mastodon, and 0.2 GitHub mentions.
No media coverage found for this CVE.
The average CVE in this peer group has 0.3 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.
Remediation records are not available for this CVE.