CVE-2021-28706

highpriority · track · 35EPSS 0.022 · 83 %ileDEEUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

2.23% (83rd) EPSS

CVSS 7.8 · high

Is it mine?

17 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · cert_bund · nvd

EPSS · scored 2026-10-27

guests may exceed their designated memory limit When a guest is permitted to have close to 16TiB of memory, it may be able to issue hypercalls to increase its memory allocation beyond the administrator established limit. This is a result of a calculation done with 32-bit precision, which may overflow. It would then only be the overflowed (and hence small) number which gets compared against the established upper bound.

cvss

Technical severity, 0–10. One row per scoring source.

8.6

010

base score 0–10 · higher = more severe · hover a vector to decode

v2.07.8highAV:N/AC:L/Au:N/C:N/I:N/A:Cprimary · NVD / NIST USexploitability 10 · impact 6.9

v3.18.6highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 4

v3.17.9highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-770USprimary

affected products (17)

Products and version ranges known to be affected.

Citrix Systems Hypervisorall versionscert_bundDEcpe:/o:citrix:hypervisor:-
Debian Linuxall versionscert_bundDEcpe:/o:debian:debian_linux:-
Gentoo Linuxall versionscert_bundDEcpe:/o:gentoo:linux:-
Open Source Xen Xen 4.12.xall versionscert_bundDEcpe:/o:xen:xen:xen_4.12.x
Open Source Xen Xen 4.13.xall versionscert_bundDEcpe:/o:xen:xen:xen_4.13.x
Open Source Xen Xen 4.14.xall versionscert_bundDEcpe:/o:xen:xen:xen_4.14.x
Open Source Xen Xen 4.15.xall versionscert_bundDEcpe:/o:xen:xen:xen_4.15.x
Oracle VMall versionscert_bundDEcpe:/a:oracle:vm:-
SUSE Linuxall versionscert_bundDEcpe:/o:suse:suse_linux:-
Xen Xen≤ 4.12.xenisa_euvdEU
Xen Xen≤ 4.13.xenisa_euvdEU
Xen Xen≤ xen-unstableenisa_euvdEU
Xen Xen4.14.x → unspecifiedenisa_euvdEU
debian debian linux= 11.0nvdUScpe:2.3:o:debian:debian_linux:*:*:*:*:*:*:*:*
fedoraproject fedora= 34nvdUScpe:2.3:o:fedoraproject:fedora:*:*:*:*:*:*:*:*
fedoraproject fedora= 35nvdUScpe:2.3:o:fedoraproject:fedora:*:*:*:*:*:*:*:*
xen xen3.2 → 4.12nvdUScpe:2.3:o:xen:xen:*:*:*:*:*:*:*:*

advisories (1)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2024-0281Xen: Mehrere SchwachstellenDeutsch2021-11-23csaf · cert_bundDE
Ein lokaler Angreifer kann mehrere Schwachstellen in Xen ausnutzen, um seine Privilegien zu erhöhen, beliebigen Programmcode auszuführen, Informationen offenzulegen oder einen Denial of Service Zustand herbeizuführen.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd cert_bund nvd NVD CVE.org MITRE

published 2021-11-24modified 2026-06-17

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+3263 more

references (27)

External citations — patches, advisories, analysis.

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