CVE-2021-3653

mediumpriority · track · 35OT risk · elevatedEPSS 0.004 · 39 %ileDEEURUUS
grimoire priorityP3 · Track
Exploitable?
—
no known exploitation
Likely / severe?
0.45% (39th) EPSS
CVSS 6.1 · medium
Is it mine?
30 products
Check your exposure
Who says so?
4 sources
cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-27

A flaw was found in the KVM's AMD code for supporting SVM nested virtualization. The flaw occurs when processing the VMCB (virtual machine control block) provided by the L1 guest to spawn/handle a nested guest (L2). Due to improper validation of the "int_ctl" field, this issue could allow a malicious L1 to enable AVIC support (Advanced Virtual Interrupt Controller) for the L2 guest. As a result, the L2 guest would be allowed to read/write physical pages of the host, resulting in a crash of the entire system, leak of sensitive data or potential guest-to-host escape. This flaw affects Linux kernel versions prior to 5.14-rc7.

01

cvss

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

8.8
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.1–8.8

v2.06.1mediumAV:L/AC:L/Au:N/C:P/I:P/A:Cprimary · NVD / NIST USexploitability 3.9 · impact 8.5
v3.18.8highCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 2 · impact 6
v3.17.5highAV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU
v3.18.1highCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)
02

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-264USCWE-862USCWE-862US
03

affected products (30)

Products and version ranges known to be affected.

showing 20 of 30
04

advisories (2)

Vendor and ecosystem advisories describing this.

  • WID-SEC-W-2022-2065Linux Kernel: Mehrere Schwachstellen ermöglichen Denial of ServiceDeutsch2021-08-16csaf · cert_bundDE

    Ein lokaler Angreifer kann mehrere Schwachstellen im Linux Kernel ausnutzen, um einen Denial of Service Angriff durchzuführen.

  • WID-SEC-W-2023-0063Juniper Junos Space: Mehrere SchwachstellenDeutsch2022-01-12csaf · cert_bundDE

    Ein Angreifer aus dem angrenzenden Netzwerk oder ein entfernter anonymer, authentisierter oder lokaler Angreifer kann mehrere Schwachstellen in Juniper Junos Space ausnutzen, um Sicherheitsmaßnahmen zu umgehen, vertrauliche Informationen offenzulegen, einen Denial-of-Service-Zustand auszulösen, beliebigen Code auszuführen und seine Privilegien zu erweitern.

05

also known as (4)

Other names and identifiers for this entity.

06

sources

Which sources assert this record, and when.

cnnvdenisa_euvdfstec_bducert_bundNVDCVE.orgMITRE
published 2021-09-29modified 2026-06-17
07

references (73)

External citations — patches, advisories, analysis.

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