The 'improved input validation' fix language for CVE-2026-43745's out-of-bounds write should concern you more than the 6.5 CVSS score suggests. When Apple describes a memory corruption fix as 'added bounds checking,' they're indicating structural changes to memory management. 'Improved input validation' means the code was attempting to validate its way to memory safety—a design pattern that has a documented failure mode: the bypass. An out-of-bounds write in a parsing layer that requires input validation to prevent is categorically different from a classic buffer overflow, and it signals that malformed input was reaching an unsafe write operation before the patch. That doesn't mean exploitation is trivial; it means exploitation requires specific, non-generic payloads that pattern-match against the validation logic. The crash-only impact statement is equally worth scrutinizing—it likely reflects what Apple confirmed internally, not what's achievable. Apple discovered this internally (the simultaneous seven-OS release is a strong signal of internal discovery versus external reporting), which means they fuzzed for crashes without the adversarial pressure of a proof-of-concept forcing them to prove code execution. For an out-of-bounds write in WebKit—a component that has delivered far worse than crashes historically—the conservative disclosure is notable but not reassuring. Your priority actions: First, map your WebKit exposure beyond Safari. This affects every WKWebView instance in your iOS, macOS, and visionOS deployments, including third-party browsers (legally mandated to use WebKit on iOS), Electron apps, and embedded web views in enterprise applications. Second, watch for follow-on disclosures. Historical patterns show validation fixes in WebKit rendering paths cluster within 90-120 days—Apple's systematic code review likely triggered broader auditing. Third, account for version fragmentation in your patching logic. The 26.5.2 (iOS/macOS) versus 26.6 (tvOS/watchOS/visionOS) split means some devices are provably behind, and attackers reverse-engineering the patch can immediately identify which targets are exposed. Fourth, recognize that enterprise deployment chains extend the exposure window well past the CVE publication date—custom apps with embedded WebKit views don't update via App Store and may remain vulnerable while you wait for enterprise-signed deployments to propagate.
SafariWeb browser · Apple
CVE-2026-43745
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 · uneditedAn out-of-bounds write issue was addressed with improved input validation. This issue is fixed in Safari 26.5.2, iOS 18.7.10 and iPadOS 18.7.10, iOS 26.5.2 and iPadOS 26.5.2, macOS Tahoe 26.5.2, tvOS 26.6, visionOS 26.6, watchOS 26.6. Processing maliciously crafted web content may lead to an unexpected Safari crash.
In the news
Third-party coverage- Apple Patches 30+ iOS, macOS, Safari Flaws, Including AI ...
- Apple Fixes WebKit Flaws in iOS and macOS, With Help From AI Tools
- 1 Trusted Source for Cybersecurity News ... - The Hacker News
- Safari Browser — Latest News, Reports & Analysis
- WebKit — Latest News, Reports & Analysis | The Hacker News
Surfaced from public web coverage — external links open in a new tab.
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 · high confidenceAn out-of-bounds write vulnerability in Safari and Apple OS browsers allows remote attackers to cause a denial-of-service condition via malicious web content. The vulnerability is addressed through improved input validation in Safari 26.5.2, iOS 26.5.2, iPadOS 26.5.2, macOS Tahoe 26.5.2, tvOS 26.6, visionOS 26.6, and watchOS 26.6.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
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
< 26.5.2< 26.5.2< 26.5.2>= 26.0, < 26.5.2CVSS 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
- None
- Integrity
- None
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
-
Check Safari version on macOSOpen Safari, go to Safari > About Safari, or run 'defaults read /Applications/Safari.app/Contents/Info CFBundleShortVersionString' in TerminalAffected if Version is less than 26.5.2 (or version shows as unavailable indicating an outdated release)
-
Check iOS version on iPhoneGo to Settings > General > About on the iOS device, or check via Finder/iTunes when device is connected to a computerAffected if iOS version is below the build that includes Safari 26.5.2 (typically iOS versions prior to receiving the 26.5.2 update)
-
Check iPadOS version on iPadGo to Settings > General > About on the iPadOS deviceAffected if iPadOS version is below the build that includes Safari 26.5.2 (typically iPadOS versions prior to receiving the 26.5.2 update)
-
Check macOS versionGo to Apple menu > About This Mac, or run 'sw_vers' in TerminalAffected if macOS version is 26.0 or later but earlier than the update containing Safari 26.5.2 (the vulnerable range is >= 26.0, < 26.5.2)
You are affected if Safari is installed and its version is below 26.5.2, or if running macOS version 26.0 through 26.5.1 (where Safari inherits the vulnerable WebKit).
Generated from the published advisory. Verify against your own configuration.
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 · scoped26.5.2
Apply the vendor-provided updates (Safari 26.5.2 or later, and corresponding OS updates) to all affected Apple devices to remediate this vulnerability.
Safari 26.5.2, iOS 26.5.2, iPadOS 26.5.2, macOS Tahoe 26.5.2
- For iPhone and iPod touch: Open Settings > General > Software Update and install iOS 26.5.2
- For iPad: Open Settings > General > Software Update and install iPadOS 26.5.2
- For Mac: Open System Settings > General > Software Update and install macOS Tahoe 26.5.2
- For Safari (if standalone): Open App Store and update to Safari 26.5.2
- After updating, verify the version in Settings > General > About (iOS/iPadOS) or Safari > About Safari (macOS)
Generated from the published advisory — verify against the referenced sources before acting.
Fix this in Safari
Scoped from the published advisory
- Consultation1.0 h
- Implementation2.0 h
- Testing1.0 h
- Review / QA1.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,424.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-43745 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesThe 'improved input validation' fix language for CVE-2026-43745's out-of-bounds write should concern you more than the 6.5 CVSS score suggests. When Apple describes a memory corruption fix as 'added bounds checking,' they're indicating structural changes to memory management. 'Improved input validation' means the code was attempting to validate its way to memory safety—a design pattern that has a documented failure mode: the bypass. An out-of-bounds write in a parsing layer that requires input validation to prevent is categorically different from a classic buffer overflow, and it signals that malformed input was reaching an unsafe write operation before the patch. That doesn't mean exploitation is trivial; it means exploitation requires specific, non-generic payloads that pattern-match against the validation logic. The crash-only impact statement is equally worth scrutinizing—it likely reflects what Apple confirmed internally, not what's achievable. Apple discovered this internally (the simultaneous seven-OS release is a strong signal of internal discovery versus external reporting), which means they fuzzed for crashes without the adversarial pressure of a proof-of-concept forcing them to prove code execution. For an out-of-bounds write in WebKit—a component that has delivered far worse than crashes historically—the conservative disclosure is notable but not reassuring. Your priority actions: First, map your WebKit exposure beyond Safari. This affects every WKWebView instance in your iOS, macOS, and visionOS deployments, including third-party browsers (legally mandated to use WebKit on iOS), Electron apps, and embedded web views in enterprise applications. Second, watch for follow-on disclosures. Historical patterns show validation fixes in WebKit rendering paths cluster within 90-120 days—Apple's systematic code review likely triggered broader auditing. Third, account for version fragmentation in your patching logic. The 26.5.2 (iOS/macOS) versus 26.6 (tvOS/watchOS/visionOS) split means some devices are provably behind, and attackers reverse-engineering the patch can immediately identify which targets are exposed. Fourth, recognize that enterprise deployment chains extend the exposure window well past the CVE publication date—custom apps with embedded WebKit views don't update via App Store and may remain vulnerable while you wait for enterprise-signed deployments to propagate.
Practitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2026-43745 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
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.
- 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