Apple macOS/iOS/iPadOS prior 26.3.1 (a)/26.3.2 (a) cross-domain policy

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.7$5k-$25k0.00

Summaryinfo

A vulnerability categorized as critical has been discovered in Apple macOS, iOS and iPadOS. Affected by this vulnerability is an unknown functionality. The manipulation results in cross-domain policy. This vulnerability is known as CVE-2026-20643. It is possible to launch the attack remotely. No exploit is available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical has been found in Apple macOS, iOS and iPadOS. Affected is an unknown functionality. The manipulation with an unknown input leads to a cross-domain policy vulnerability. CWE is classifying the issue as CWE-942. The product uses a cross-domain policy file that includes domains that should not be trusted. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

A cross-origin issue in the Navigation API was addressed with improved input validation. This issue is fixed in Background Security Improvements for iOS, iPadOS, and macOS, Safari 26.4, iOS 18.7.7 and iPadOS 18.7.7, iOS 26.4 and iPadOS 26.4, macOS Tahoe 26.4, visionOS 26.4. Processing maliciously crafted web content may bypass Same Origin Policy.

The advisory is available at support.apple.com. This vulnerability is traded as CVE-2026-20643 since 11/11/2025. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. Successful exploitation requires user interaction by the victim. The technical details are unknown and an exploit is not available. The structure of the vulnerability defines a possible price range of USD $5k-$25k at the moment (estimation calculated on 03/28/2026).

The vulnerability scanner Nessus provides a plugin with the ID 304118 (Linux Distros Unpatched Vulnerability : CVE-2026-20643), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 26.3.1 (a) or 26.3.2 (a) eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (304118) and CERT Bund (WID-SEC-2026-0762). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

  • Apple iOS
  • Apple iPadOS
  • Apple macOS

Productinfo

Type

Vendor

Name

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.9
VulDB Meta Temp Score: 5.7

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

ADP CISA Base Score: 5.4
ADP CISA Vector: 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Cross-domain policy
CWE: CWE-942 / CWE-346 / CWE-345
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 304118
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-20643

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: macOS/iOS/iPadOS 26.3.1 (a)/26.3.2 (a)

Timelineinfo

11/11/2025 CVE reserved
03/18/2026 +127 days Advisory disclosed
03/18/2026 +0 days VulDB entry created
03/28/2026 +10 days VulDB entry last update

Sourcesinfo

Vendor: apple.com

Advisory: support.apple.com
Status: Confirmed

CVE: CVE-2026-20643 (🔒)
GCVE (CVE): GCVE-0-2026-20643
GCVE (VulDB): GCVE-100-351450
CERT Bund: WID-SEC-2026-0762 - Apple iOS, iPadOS und macOS: Schwachstelle ermöglicht Umgehen von Sicherheitsvorkehrungen

scip Labs: https://www.scip.ch/en/?labs.20180712

Entryinfo

Created: 03/18/2026 02:57
Updated: 03/28/2026 10:23
Changes: 03/18/2026 02:57 (53), 03/18/2026 12:12 (7), 03/21/2026 22:36 (13), 03/25/2026 04:03 (1), 03/28/2026 10:23 (2)
Complete: 🔍
Cache ID: 216:0D9:103

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