SafariWeb browser · Apple

CVE-2026-43821

MEDIUM · 6.5 CVSS v3.1 Published 2026-07-27
Fix available
A fix is available. Upgrade to 26.6 or later.
See remediation →
72/100
Remediation priority · Elevated
Remotely reachable No privileges 3 weeks old

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
An access issue was addressed with improved access restrictions. This issue is fixed in Safari 26.6, iOS 18.7.10 and iPadOS 18.7.10, iOS 26.6 and iPadOS 26.6, macOS Tahoe 26.6, tvOS 26.6, visionOS 26.6, watchOS 26.6. An app may be able to read files outside of its sandbox.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis
How this class of weakness works · CWE-284

The application fails to correctly restrict what a user can do or reach, so functions or resources are available to people who should not have them. Attackers simply probe for the paths where the check is missing or wrong. The fix is to enforce access-control decisions consistently on every request, evaluated against the acting user rather than assumed from context.

General guidance for the improper access control class — the official description and references above are authoritative for this specific CVE. Want a bespoke review and a reviewed fix? Ask our team →

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
SafariWeb browser
Affected:< 26.6
IpadosOperating system
Affected:< 26.6
Iphone OsOperating system
Affected:< 26.6
macOSOperating system
Affected:>= 26.0, < 26.6
TvosOperating system
Affected:< 26.6
VisionosOperating system
Affected:< 26.6
WatchosOperating system
Affected:< 26.6

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 26.6 or later
Fixed in 26.6
Recommended fix High confidence

Upgrade to Safari 26.6, iOS 26.6, iPadOS 26.6, macOS Tahoe 26.6, tvOS 26.6, visionOS 26.6, or watchOS 26.6 depending on the product

  1. Identify the Apple device type (Safari, iOS, iPadOS, macOS, tvOS, visionOS, or watchOS) that needs to be updated
  2. Check the current installed version of the software on the device
  3. Update the software to the fixed version: Safari 26.6, iOS 26.6, iPadOS 26.6, macOS Tahoe 26.6, tvOS 26.6, visionOS 26.6, or watchOS 26.6 depending on the device
  4. For iOS/iPadOS devices: Go to Settings > General > Software Update and install the update
  5. For macOS: Go to System Preferences > Software Update (or System Settings > General > Software Update on newer macOS) and install the update
  6. For Safari: Update via macOS system update to receive Safari 26.6
  7. For tvOS/visionOS/watchOS: Go to Settings > General > Software Update and install the update
  8. Restart the device if prompted to complete the installation

Generated from the published advisory — verify against the referenced sources before acting.

We can perform the upgrade in your staging environment and verify nothing breaks — typical engagement from $1,600. Get the upgrade done

Scan for this in your stack

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-43821 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data