CVE-2023-40394

Sensitive user-data access via environment-variable validation

Published Jan 10, 2024 · Updated Jun 20, 2025

Improper input validation in Apple iOS and iPadOS before 16.6 allows local users to access sensitive user data through a malicious app. The Logging component insufficiently validates environment variables before processing them, but Apple has not disclosed the affected function or data path. Exploitation requires a user to run an app on an affected device, and the disclosed consequence is limited to sensitive user-data access.

CVSS severity3.3
Low
EPSS probability0.20%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper input validation in Apple iOS and iPadOS before 16.6 allows local users to access sensitive user data through a malicious app. The Logging component insufficiently validates environment variables before processing them, but Apple has not disclosed the affected function or data path. Exploitation requires a user to run an app on an affected device, and the disclosed consequence is limited to sensitive user-data access.

The record

CVE
CVE-2023-40394
Published
Jan 10, 2024
Updated
Jun 20, 2025
Vendor
Apple
Product
iOS and iPadOS
Classifications
CWE-20, T1533
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 10, 2024CVE publishedPublication date reported by the CVE source.
  2. Jun 20, 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=unspecified <16.6

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Apple · iOS and iPadOSversion=unspecified <16.6

Published CVSS scores

3.3NIST NVDCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
3.3CISA-ADPCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N

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.

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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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-20Improper Input Validation
T1533Data 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

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Your stack

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