Apple Multiple Products Improper Certificate Validation Vulnerability (CVE-2023-41991)

Apple iOS, iPadOS, macOS, and watchOS contain an improper certificate validation vulnerability that can allow a malicious app to bypass signature validation.

Published Sep 21, 2023 · Updated May 29, 2026

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Why patchRisk explained in plain English

Worst-case scenarioIf unpatched

A local attacker, without authentication, can achieve partial data exposure, arbitrary modification of data. Federal agencies are required to remediate by 2023-10-16 under CISA BOD 22-01.

How the attack worksNo clicks needed

This is a Improper Certificate Validation (CWE-295) vulnerability in Apple Multiple Products. A certificate validation issue was addressed. This issue is fixed in macOS Ventura 13.6, iOS 16.7 and iPadOS 16.7. A malicious app may be able to bypass signature validation. Apple is aware of a report that this issue may have been actively exploited against versions of iOS before iOS 16.7. Exploitation requires local access, low attack complexity, no authentication required, and user interaction required.

Am I affected?Quick check

Probably yes if any of these apply:

●Apple Device Administrators

●Endpoint Security

●IT Security

●Running ipados: v < 16.7, 17.0; iphone os: v < 16.7, 17.0; macos: 13.0 ≤ v < 13.6

Real-world incidentsWhat we've seen

CISA added this CVE to the Known Exploited Vulnerabilities catalog on 2023-09-25 based on evidence of active exploitation in the wild. Federal agencies required to remediate by 2023-10-16.

How to patch

Get the fix

Apply the fixed package from your vendor. The advisory lists affected versions and the exact fixed build.

↗ Vendor advisory

Manual remediation steps

Identify affected hosts: query inventory for general installs in scope.

Apply the vendor security update referenced in CVE-2023-41991's advisory. No specific KB/version is encoded yet — consult the linked MSRC/vendor URL.

Verify the fix per the vendor's published verification steps.

Document the remediation in your change ticket and re-scan with your vulnerability scanner to confirm closure.

PowerShell automationComing soon

No tested PowerShell script for this entry yet. We’re prioritising automation based on user demand.

References