CVE-2022-33742

Guest-memory disclosure via whole-page block grants

Published Jul 5, 2022 · Updated Aug 3, 2024

Information disclosure in the Linux kernel Xen block frontend allows attackers controlling a PV backend to read unrelated guest memory. The xen-blkfront driver grants whole 4 KiB pages when an I/O request covers only part of a page, exposing contiguous data outside the request fragments. Exploitation requires a Linux guest using a Xen PV block device with a potentially malicious backend; writable grants also permit corruption that can malfunction or crash consumers.

CVSS severity7.1
High
EPSS probability0.33%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Information disclosure in the Linux kernel Xen block frontend allows attackers controlling a PV backend to read unrelated guest memory. The xen-blkfront driver grants whole 4 KiB pages when an I/O request covers only part of a page, exposing contiguous data outside the request fragments. Exploitation requires a Linux guest using a Xen PV block device with a potentially malicious backend; writable grants also permit corruption that can malfunction or crash consumers.

The record

CVE
CVE-2022-33742
Published
Jul 5, 2022
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-200, T1005
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Jul 5, 2022CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

7.1NISTCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
3.6NISTAV:L/AC:L/Au:N/C:P/I:N/A:P
7.1CanonicalCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-200Exposure of Sensitive Information to an Unauthorized Actor
T1005Data from Local System

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo