CVE-2021-4093

HIGH
8.8
CVSS Score
Published: February 18, 2022 at 05:50 PM UTC
Updated: June 17, 2026 at 04:19 AM UTC
5 products affected across 4 vendorsLinux KernelFedoraUbuntu Linux

Using kernel by N/A?

Get instant alerts when new vulnerabilities affect kernel - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Severity
HIGH8.8
Exploit prediction
EPSS 0.4%

Description

A flaw was found in the KVM's AMD code for supporting the Secure Encrypted Virtualization-Encrypted State (SEV-ES). A KVM guest using SEV-ES can trigger out-of-bounds reads and writes in the host kernel via a malicious VMGEXIT for a string I/O instruction (for example, outs or ins) using the exit reason SVM_EXIT_IOIO. This issue results in a crash of the entire system or a potential guest-to-host escape scenario.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

5.11 ≤ v < 5.14.16
Affected range stops below 5.14.16, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (2)

x_refsource_MISCExploitMailing ListPatchThird Party Advisory
https://bugs.chromium.org/p/project-zero/issues/detail?id=2222
x_refsource_MISCIssue TrackingPatchThird Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2028584

CVSS

Attack Vector
LOCAL
Complexity
LOW
Privileges
LOW
User Interaction
NONE
Scope
CHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-125

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Free plan, no card