CVE-2025-46299 Overview
CVE-2025-46299 is a memory initialization vulnerability affecting Apple Safari and multiple Apple operating systems. Processing maliciously crafted web content may disclose internal application states, exposing sensitive memory contents to attackers. The flaw is classified as an information disclosure issue rooted in improper access control [CWE-284].
Apple addressed the vulnerability by improving memory handling in Safari 26.2, iOS 26.2, iPadOS 26.2, macOS Tahoe 26.2, tvOS 26.2, visionOS 26.2, and watchOS 26.2. Exploitation requires user interaction, typically visiting a malicious webpage. No public proof-of-concept or in-the-wild exploitation has been reported.
Critical Impact
Attackers can leverage crafted web content to leak internal app states from Safari and WebKit-backed applications across Apple's device ecosystem.
Affected Products
- Apple Safari (prior to 26.2)
- Apple iOS and iPadOS (prior to 26.2)
- Apple macOS Tahoe, tvOS, visionOS, and watchOS (prior to 26.2)
Discovery Timeline
- 2026-01-09 - CVE-2025-46299 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-46299
Vulnerability Analysis
The vulnerability stems from uninitialized memory being accessed during web content processing. When Safari or another WebKit-based application parses attacker-controlled content, portions of memory that have not been properly initialized can be read and returned to the rendering context. This exposes residual data left over from prior allocations.
The issue falls under the improper access control category [CWE-284] and is exploitable across Apple's product line because the affected component is shared through WebKit. The attack vector is network-based and requires the victim to open a malicious page, but does not require authentication.
The EPSS score is 0.266% with a percentile of 17.968, indicating a low likelihood of near-term exploitation activity.
Root Cause
Memory buffers used during web content parsing were not fully initialized before being read. Uninitialized memory use [CWE-908] permits leakage of pointer values, object metadata, or heap contents that should remain private to the process. Apple's fix ensures buffers are zeroed or otherwise properly initialized before consumption.
Attack Vector
An attacker hosts a malicious website or embeds crafted content in a page loaded by the victim. When the target browses to the page using a vulnerable Safari or WebKit-backed application, the rendering engine processes the payload and inadvertently returns uninitialized memory to attacker-controllable script contexts. The disclosed data can aid further exploitation by defeating address space layout randomization (ASLR) or revealing sensitive state.
No public exploitation code or proof-of-concept has been released. See the Apple Security Advisory #125884 for vendor technical context.
Detection Methods for CVE-2025-46299
Indicators of Compromise
- Safari or WebKit-based application versions below 26.2 loading untrusted third-party web content.
- Unexpected outbound connections from browser processes to unfamiliar domains hosting scripted content.
- Crash reports or telemetry entries in WebKit processes referencing anomalous memory reads during rendering.
Detection Strategies
- Inventory Apple endpoints and enumerate installed Safari, iOS, iPadOS, macOS, tvOS, visionOS, and watchOS versions to identify systems below 26.2.
- Monitor endpoint telemetry for browser process behavior deviating from baseline, particularly memory-related anomalies in WebKit.
- Correlate DNS and proxy logs with threat intelligence feeds to flag connections to known malicious content delivery domains.
Monitoring Recommendations
- Enable centralized logging for macOS and iOS device management platforms to track OS version compliance.
- Alert on Safari or WebKit process crashes that could indicate exploitation attempts.
- Track user interaction patterns leading to unexpected sensitive data access following browser sessions.
How to Mitigate CVE-2025-46299
Immediate Actions Required
- Update all Apple devices to Safari 26.2, iOS 26.2, iPadOS 26.2, macOS Tahoe 26.2, tvOS 26.2, visionOS 26.2, or watchOS 26.2.
- Prioritize patching endpoints used for browsing untrusted content or handling sensitive data.
- Communicate the risk of clicking untrusted links to end users until patching completes.
Patch Information
Apple released fixes in the 26.2 update train across Safari and all supported operating systems. Refer to the following advisories for version-specific guidance: Apple Security Advisory #125884, #125886, #125889, #125890, #125891, and #125892.
Workarounds
- Restrict Safari usage on unpatched devices to trusted internal sites via mobile device management (MDM) content filtering.
- Deploy web proxies that block known malicious domains and enforce category-based browsing policies.
- Educate users to avoid opening links from untrusted sources until updates are applied.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
