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Full vulnerability report · 2026
CVE-2026-20643High confidence

Processing maliciously crafted web content may bypass Same Origin Policy

Apple · Safari

5.4MediumCVSS 3.1
Recommended action
Scheduled

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.

Fix not verified
Distribution package intelligence

Ubuntu vendor package status

Canonical’s release and source-package findings are shown separately from local repository availability.

2 package states
Repository candidate not checked

A published vendor fix does not prove that a matching update is enabled and installable on a particular asset. Confirm the local package candidate before scheduling remediation.

Ubuntu releaseSource packageVendor stateFixed versionEvidence
Ubuntu 24.04 LTSnoble · standard archiveqtwebkit-opensource-srcUnder evaluationCanonical reports that the package might be affected and still needs evaluation or fixing.Not published in this feedCanonical record ↗Source updated 8 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivewebkit2gtkVendor fix publishedCanonical reports that a fixed source package version has been published. Repository candidate availability is not checked by BlackTree.2.52.3-0ubuntu0.24.04.1Canonical record ↗Source updated 8 Sept 2026
Optional official sources

National CERT insights
?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

Select the national-authority views to include. The exact source language is shown on each matched advisory. Your choice is remembered on this device and encoded in the shareable URL.

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current
ENISA EUVD identifier

EUVD-2026-12663

No EUVD known-exploited evidence

ENISA has published the identifier mapping but no EUVD description has been stored yet.

EUVD state
Present in the current official mapping
Known exploitation
Not present in the current ENISA EUVD known-exploited dataset. This is not proof of no exploitation.
ENISA score
Not supplied in the stored EUVD record
Advisory evidence
No linked advisory details stored yet
Recommended actionScheduled

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.

Fix not verified
01

What, why and how

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.

What

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.

Why

The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.

How

An attacker operating through a network path may attempt exploitation without authentication after a user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

What

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.

Why

The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.

How

An attacker operating through a network path may attempt exploitation without authentication after a user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

02

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
No confirmed evidence

No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.

Public PoC / exploit material
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
None recorded

No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.

Likely attack path
a network path → Improper Input Validation → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Network
Privileges required
None: unauthenticated exploitation is possible
User interaction
Required interaction required
Attack complexity
Low: no specialised conditions are recorded
Security boundary
Unchanged: impact remains within the vulnerable component's security authority
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-20

CWE-20: Improper Input Validation. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N

Common Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.

AVNetworkAttack vector: The vulnerable component can be reached over a network.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRNonePrivileges required: The attacker does not need an account or existing privileges.UIRequiredUser interaction: Another user must perform an action for exploitation to succeed.SUnchangedScope: The security impact remains within the vulnerable component's authority.CLowConfidentiality impact: A successful attack can cause a limited loss.ILowIntegrity impact: A successful attack can cause a limited loss.ANoneAvailability impact: No direct loss is represented by this metric.
Post-exploitation / living off the land
No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
NetworkUnauthenticatedCWE-20
A

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

BSI · German · WID-SEC-W-2026-0848Apple Safari: Mehrere Schwachstellen

Ein Angreifer kann mehrere Schwachstellen in Apple Safari ausnutzen, um Sicherheitsvorkehrungen zu umgehen, um einen Denial of Service Angriff durchzuführen, um Informationen offenzulegen, und um einen Cross-Site Scripting Angriff durchzuführen.

Official advisory
BSI · German · WID-SEC-W-2026-0852Apple iOS: Mehrere Schwachstellen

Ein Angreifer kann mehrere Schwachstellen in Apple iOS und Apple iPadOS ausnutzen, um Sicherheitsvorkehrungen zu umgehen, um einen Denial of Service Angriff durchzuführen, um Informationen offenzulegen, und um einen Cross-Site Scripting Angriff durchzuführen.

Official advisory
BSI · German · WID-SEC-W-2026-0853Apple macOS: Mehrere Schwachstellen

Ein Angreifer kann mehrere Schwachstellen in Apple macOS ausnutzen, um Sicherheitsvorkehrungen zu umgehen, um einen Denial of Service Angriff durchzuführen, um Informationen offenzulegen, um Dateien zu manipulieren, und um seine Privilegien zu erhöhen.

Official advisory
BSI · German · WID-SEC-W-2026-0762Apple iOS, iPadOS und macOS: Schwachstelle ermöglicht Umgehen von Sicherheitsvorkehrungen

Ein entfernter, anonymer Angreifer kann eine Schwachstelle in Apple iOS, Apple iPadOS und Apple macOS ausnutzen, um Sicherheitsvorkehrungen zu umgehen.

Official advisory
BSI · German · WID-SEC-W-2026-0911WebKitGTK: Mehrere Schwachstellen

Ein Angreifer kann mehrere Schwachstellen in WebKitGTK ausnutzen, um einen Denial of Service Angriff durchzuführen, um Sicherheitsvorkehrungen zu umgehen, um Informationen offenzulegen, und um einen Cross-Site Scripting Angriff durchzuführen.

Official advisory
CERT-FR · French · CERTFR-2026-AVI-0355Multiples vulnérabilités dans les produits Apple

d?id=CVE-2025-64505 Référence CVE CVE-2025-65082 https://www.cve.org/CVERecord?id=CVE-2025-65082 Référence CVE CVE-2025-66200 https://www.cve.org/CVERecord?id=CVE-2025-66200 Référence CVE CVE-2026-20607 https://www.cve.org/CVERecord?id=CVE-2026-20607 Référence CVE CVE-2026-20631 https://www.cve.org/CVERecord?id=CVE-2026-20631 Référence CVE CVE-2026-20632 https://www.cve.org/CVERecord?id=CVE-2026-20632 Référence CVE CVE-2026-20633 https://www.cve.org/CVERecord?id=CVE-2026-20633 Référence CVE CVE-2026-20637 https://www.cve.org/CVERecord?id=CVE-2026-20637 Référence CVE CVE-2026-20639 https://www.cve.org/CVERecord?id=CVE-2026-20639 Référence CVE CVE-2026-20643 https://www.cve.org/CVERecord?id=CVE-2026-20643 Référence CVE CVE-2026-20651 https://www.cve.org/CVERecord?id=CVE-2026-20651 Référence CVE CVE-2026-20657 https://www.cve.org/CVERecord?id=CVE-2026-20657 Référence CVE CVE-2026-20660 https://www.cve.org/CVERecord?id=CVE-2026-20660 Référence CVE CVE-2026-20664 https://www.cve.org/CVERecord?id=CVE-2026-20664 Référence CVE CVE-2026-20665 https://www.cve.org/CVERecord?id=CVE-2026-20665 Référence CVE CVE-2026-20668 https://www.cve.org/CVERecord?id=CVE-2026-20668 Référence CVE CVE-2026-20684 https://www.cve.org/CVERecord?id=CVE-2026-20684 Référence CVE CVE-2026-20687 https://www.cve.org/CVERecord?id=

Official advisory
CERT-FR · French · CERTFR-2026-AVI-0313Vulnérabilité dans les produits Apple

Une vulnérabilité a été découverte dans les produits Apple. Elle permet à un attaquant de provoquer un contournement de la politique de sécurité.

Official advisory
NCSC-NL · Dutch · NCSC-2026-0102Kwetsbaarheden verholpen in Apple macOS

Multiple Apple OS updates including Safari, iOS, iPadOS, and macOS addressed a cross-origin vulnerability in the Navigation API by improving input validation to prevent bypassing the Same Origin Policy.

Official advisory
03

Patch and workaround

Operational remediation based on structured source evidence.

Status
?Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.
Fix not verified
Affected
< 26.4; < 18.7.7; < 26.3.1 (a); < 26.3.2 (a)
Fixed
No fixed version is explicitly recorded in the structured CVE data.
Action
No verified patch reference is present in the current structured sources. Check the vendor advisory before making a change.
Workaround
No verified workaround is recorded. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
04

Evidence and provenance

Published 17 Mar 2026 · Last source change 17 Aug 2026, 21:30 UTC · CWE-20 · Improper Input Validation

CVE recordCVE.org · 5.2
CVSS sourceCISA ADP
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-08-14
European sourceENISA EUVD · EUVD-2026-12663
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceCISA ADP
NVD statusNVD modified after enrichment

Core structured fields are present and their contributing authorities are shown above.

Material change intelligence

What changed after publication

View recent updates →

No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.

Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
Technical terms and abbreviations used in this report
CVE
Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS
Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS
Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE
Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA
CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP
Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD
National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT
A computer security incident response team that publishes warnings or coordinates incident response.
PoC
Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF
Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL
Living off the land: abuse of legitimate tools or system functions during an attack.
Free version - for non-commercial use only.CVE-2026-20643 · cve.blacktree.nl