CVE-2025-43429 Overview
CVE-2025-43429 is a buffer overflow vulnerability affecting Apple Safari and multiple Apple operating systems. Processing maliciously crafted web content may lead to an unexpected process crash. Apple addressed the issue with improved bounds checking across its product line.
The vulnerability requires user interaction, such as visiting a malicious web page, and can be triggered over the network. Successful exploitation results in a denial of service condition through process termination, without granting confidentiality or integrity impact.
Critical Impact
Processing maliciously crafted web content can trigger an unexpected process crash on unpatched Apple devices, resulting in denial of service.
Affected Products
- Apple Safari (prior to 26.1)
- Apple iOS and iPadOS (prior to 18.7.2 and 26.1)
- Apple macOS Tahoe, tvOS, visionOS, and watchOS (prior to 26.1)
Discovery Timeline
- 2025-11-04 - CVE-2025-43429 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-43429
Vulnerability Analysis
CVE-2025-43429 is classified under [CWE-119], improper restriction of operations within the bounds of a memory buffer. The flaw resides in web content processing components shared across Safari and Apple operating systems, likely within the WebKit rendering engine.
When the browser parses specially crafted web content, insufficient bounds checking allows data to exceed the allocated buffer. This corruption destabilizes the process and forces termination. The impact is limited to availability, with no observed disclosure of memory contents or code execution paths in Apple's advisory.
The EPSS probability is approximately 1.38%, placing it in the 68th percentile for likelihood of exploitation activity.
Root Cause
The root cause is missing or inadequate boundary validation in a routine that processes untrusted web content. Apple's fix introduces improved bounds checking to constrain memory operations within the intended buffer size. Without this check, attacker-controlled input can write beyond the allocated region and trigger a crash.
Attack Vector
The attack vector is network-based and requires user interaction. An attacker hosts a malicious page or embeds crafted content in an advertisement or iframe. When a victim using a vulnerable Apple device or Safari version loads the content, the buffer overflow triggers and terminates the rendering process.
No public proof-of-concept, exploit code, or CISA KEV listing exists for this CVE at the time of publication. Refer to the Apple Support Advisory #125632 and related advisories for technical fix details.
Detection Methods for CVE-2025-43429
Indicators of Compromise
- Unexpected Safari or WebKit-based process crashes recorded in system diagnostic reports on macOS, iOS, iPadOS, or related Apple platforms.
- Repeated crash reports referencing WebKit content processes shortly after visiting untrusted URLs.
- Browser navigation to unfamiliar domains immediately preceding rendering process termination.
Detection Strategies
- Monitor endpoint telemetry for abnormal termination of Safari or WebKit helper processes correlated with user browsing activity.
- Inspect crash logs under ~/Library/Logs/DiagnosticReports/ on macOS for signatures consistent with buffer overflow aborts.
- Correlate DNS and proxy logs with crash events to identify malicious URLs delivering crafted content.
Monitoring Recommendations
- Track OS build versions across the fleet to identify devices still running Safari, iOS, iPadOS, macOS, tvOS, visionOS, or watchOS versions below the patched releases.
- Alert on high-frequency browser crashes on a single device, which may indicate targeted exploitation attempts.
- Aggregate mobile device management (MDM) compliance reports to confirm patch adoption across managed Apple endpoints.
How to Mitigate CVE-2025-43429
Immediate Actions Required
- Update Safari to version 26.1 on supported macOS releases.
- Upgrade iOS and iPadOS devices to 18.7.2 or 26.1, and macOS systems to Tahoe 26.1.
- Apply the 26.1 updates for tvOS, visionOS, and watchOS on all affected devices.
- Enforce update compliance through MDM policies for managed Apple fleets.
Patch Information
Apple released fixes in Safari 26.1, iOS 18.7.2 and iPadOS 18.7.2, iOS 26.1 and iPadOS 26.1, macOS Tahoe 26.1, tvOS 26.1, visionOS 26.1, and watchOS 26.1. Details are documented in Apple Support Advisory #125633, #125634, #125637, #125638, #125639, and #125640.
Workarounds
- Restrict browsing to trusted sites until affected devices receive the vendor patch.
- Deploy web filtering or DNS-based blocklists to reduce exposure to malicious web content.
- Disable JavaScript for untrusted sites in Safari settings where operationally feasible to reduce attack surface against WebKit parsing flaws.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
