CVE-2022-35821Public exploit

Kernel memory disclosure via unchecked FDT mapping

Published Aug 9, 2022 · Updated Jan 2, 2025

Out-of-bounds read in Microsoft Azure Sphere before 22.07 allows local users with root access to disclose kernel memory. The Azure Sphere-specific simple_mmap handler maps the caller-supplied length for /proc/fdt without checking it against the FDT size. Root access on the device is required, but no extra Linux or Azure Sphere capability is needed; an oversized mapping can expose the full kernel memory image.

CVSS severity4.4
Medium
EPSS probability1.05%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Out-of-bounds read in Microsoft Azure Sphere before 22.07 allows local users with root access to disclose kernel memory. The Azure Sphere-specific simple_mmap handler maps the caller-supplied length for /proc/fdt without checking it against the FDT size. Root access on the device is required, but no extra Linux or Azure Sphere capability is needed; an oversized mapping can expose the full kernel memory image.

The record

CVE
CVE-2022-35821
Published
Aug 9, 2022
Updated
Jan 2, 2025
Vendor
Microsoft
Product
Azure Sphere
Classifications
CWE-119, T1005
Attack vector
local
Privileges
admin

Timeline

How it unfolded

  1. Aug 9, 2022CVE publishedPublication date reported by the CVE source.
  2. Jan 2, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=20.00 <22.07

What conditions does exploitation require?

Attack vectorlocal
Required privilegesadmin

What is affected?

Microsoft · Azure Sphereversion=20.00 <22.07

Published CVSS scores

4.4Microsoft CorporationCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

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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
Privilegesadmin
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-119Improper Restriction of Operations within the Bounds of a Memory Buffer
T1005Data from Local System

Public exploit references

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

Technologies

Your stack

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Your stack

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