Low

Sensitive User Data Access in iOS/iPadOS via Environment Variable Validation

IdentifiersCVE-2023-40394CWE-73

CVE-2023-40394 is an Apple iOS/iPadOS vulnerability affecting iPhone 8 and later and multiple supported iPad models. According to the provided Apple advisory content, the issue could allow a local app to access sensitive user data. Apple states the issue was addressed through improved validation of environment variables, indicating the flaw involved insufficient validation or restriction of environment-variable-controlled input in a way that exposed protected data to an app.

For your environment

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ANALYST BRIEF

Impact, mitigation & remediation

What it means. What to do now. Patch path, mitigations, and the assume-compromise checklist.

Impact

What an attacker gets, and what they’ve been doing with it.

Successful exploitation may allow a malicious app to access sensitive user data that should not be available to it under normal platform security boundaries. The provided content does not further specify the exact data types beyond 'sensitive user data,' but the impact is a confidentiality breach affecting user privacy.

Mitigation

If you can’t patch tonight, do this now.

Until patching is completed, reduce exposure by limiting installation of untrusted or unnecessary apps, especially on affected iPhone and iPad devices. Because the issue is described as exploitable by an app, maintaining strict application control and minimizing local app attack surface are the primary mitigations available from the provided information.

Remediation

Patch, then assume compromise.

Upgrade affected devices to iOS 16.6 or iPadOS 16.6, where Apple states the issue is fixed through improved validation of environment variables.

PUBLIC EXPLOITS

Exploits

No public exploits tracked yet. Mallory keeps watching.

VALID 0 / 0 TOTALView more in app

No public exploit code observed for this vulnerability.

EXPOSURE SURFACE

Affected products & vendors

Products and vendors Mallory has correlated with this vulnerability. Open in Mallory to drill down to specific CPE configurations and version ranges.

VendorProductType

AppleIpadosoperating_system

AppleIphone Osoperating_system

Vendor-confirmed product mapping. Mallory continuously reconciles this list against your asset inventory.

ACTIVITY FEED

Recent activity

2 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.

2 SOURCESView more in app

apple supportNews

Jan 25, 2026

About the security content of iOS 16.6 and iPadOS 16.6 - Apple Support

An issue involving insufficient validation of environment variables that could allow an app to access sensitive user data.

apple supportNews

Jan 19, 2026

Informazioni sui contenuti di sicurezza di iOS 16.6 e iPadOS 16.6 - Supporto Apple (IT)

Vulnerabilità di sandbox escape che può consentire a un'app di uscire dalla sandbox; corretta con miglioramenti al protocollo di gestione file.

What this page doesn’t show

The version that knows your environment.

This page is what’s public. Mallory adds the parts that aren’t: which of your assets are affected, which adversaries are exploiting it right now, which detections to deploy, and what to do tonight.

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Exposure mapping

Query your assets running an affected version, and investigate the blast radius.

Threat actor evidence

Every observed campaign linking this CVE to a named adversary.

Associated malware

Malware families riding this exploit, with evidence and IOCs.

Detection signatures

YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.

Vendor-by-vendor mapping

Cross-references every affected SKU, including bundled OEM variants.

Social activity