CVE-2025-43441: Apple Safari DOS Vulnerability Explained

CVE-2025-43441 Overview

CVE-2025-43441 is a memory handling vulnerability affecting Apple Safari and multiple Apple operating systems that share the WebKit rendering engine. Processing maliciously crafted web content may lead to an unexpected process crash, resulting in a denial-of-service condition for the browser or web view. Apple addressed the issue with improved memory handling in Safari 26.1, iOS 18.7.2, iPadOS 18.7.2, iOS 26.1, iPadOS 26.1, macOS Tahoe 26.1, tvOS 26.1, and visionOS 26.1. The flaw is categorized under [CWE-119] (Improper Restriction of Operations within the Bounds of a Memory Buffer) and [CWE-120] (Buffer Copy without Checking Size of Input).

Critical Impact
An attacker who convinces a user to visit a malicious web page can trigger an unexpected process crash, causing a denial-of-service condition on affected Apple devices.

Affected Products

Apple Safari (versions prior to 26.1)
Apple iOS and iPadOS (prior to 18.7.2 and 26.1)
Apple macOS Tahoe (prior to 26.1), tvOS (prior to 26.1), and visionOS (prior to 26.1)

Discovery Timeline

2025-11-04 - CVE-2025-43441 published to NVD
2026-07-15 - Last updated in NVD database

Technical Details for CVE-2025-43441

Vulnerability Analysis

The vulnerability resides in the memory handling logic used when Safari and other WebKit-based components parse and render web content. When a user loads specifically crafted web content, improper memory buffer operations lead to an unexpected process termination. The flaw requires user interaction, as the victim must navigate to attacker-controlled content or open a page that references it. Because the issue is limited to availability, an attacker cannot use it directly to disclose data or execute code, but repeated crashes can disrupt normal browsing and content rendering across iOS, iPadOS, macOS, tvOS, and visionOS.

Root Cause

Apple's advisory attributes the flaw to insufficient memory handling in the WebKit engine. The associated CWE mappings, [CWE-119] and [CWE-120], indicate that operations on a memory buffer exceed the intended bounds, likely due to a missing or incorrect size check during a copy or access operation. Apple resolved the issue by tightening the bounds and size validation logic in the affected code path.

Attack Vector

Exploitation occurs over the network and requires user interaction. An attacker hosts malicious HTML, JavaScript, or other web assets and lures the target into visiting the resource through phishing, malvertising, or a compromised website. When the WebKit process parses the crafted content, the memory handling flaw triggers and the rendering process crashes. Verified proof-of-concept code and public exploits are not currently available, and the vulnerability is not listed in the CISA Known Exploited Vulnerabilities catalog.

No verified proof-of-concept code is available for CVE-2025-43441. Refer to the Apple Support Advisory #125632 and Red Hat CVE Details CVE-2025-43441 for vendor technical details.

Detection Methods for CVE-2025-43441

Indicators of Compromise

Repeated or unexplained crashes of the Safari or WebKit rendering process across managed Apple endpoints.
Crash reports referencing WebKit components generated shortly after users visit external or untrusted URLs.
Web content requests to newly registered or low-reputation domains preceding browser process termination.

Detection Strategies

Monitor endpoint telemetry for abnormal com.apple.WebKit or Safari process exits and correlate with the URL loaded at the time of the crash.
Inspect macOS and iOS diagnostic reports for EXC_BAD_ACCESS or memory-related fault signatures in WebKit frames.
Use web proxy or DNS logs to identify user navigation patterns that consistently precede browser crashes.

Monitoring Recommendations

Track Apple software version inventory to identify endpoints still running Safari, iOS, iPadOS, macOS, tvOS, or visionOS builds below the patched releases.
Alert on Safari or WebKit process crash frequency exceeding baseline thresholds across the fleet.
Correlate browser crash events with threat intelligence on malicious domains and phishing campaigns.

How to Mitigate CVE-2025-43441

Immediate Actions Required

Update Safari to version 26.1 and upgrade Apple operating systems to iOS 18.7.2, iPadOS 18.7.2, iOS 26.1, iPadOS 26.1, macOS Tahoe 26.1, tvOS 26.1, or visionOS 26.1.
Deploy the corresponding Red Hat errata (for example, RHSA-2025:22789 and RHSA-2025:23110) on Linux systems that ship WebKitGTK or related components.
Instruct users to avoid untrusted links and enforce phishing awareness training to reduce the likelihood of triggering the flaw.

Patch Information

Apple published fixes across multiple advisories, including Apple Support Advisory #125632, #125633, #125634, #125637, #125638, and #125640. Red Hat tracks the issue with corresponding errata and the Red Hat CVE Details CVE-2025-43441 page. Apply the vendor updates through standard patch management workflows and validate that endpoints report the fixed version after deployment.

Workarounds

Restrict browsing to trusted sites through web filtering or secure web gateway policies until patches are applied.
Configure enterprise MDM policies to enforce minimum Safari and OS versions on managed Apple devices.
Consider temporarily using an alternative, fully patched browser on unmanaged devices that cannot be updated immediately.

bash

# Verify Safari and macOS versions on a managed endpoint
sw_vers
defaults read /Applications/Safari.app/Contents/Info.plist CFBundleShortVersionString