Description

The issue was addressed with improved input validation. This issue is fixed in iOS 18.7.10 and iPadOS 18.7.10, iOS 26.6.1 and iPadOS 26.6.1, macOS Tahoe 26.6.2. Processing maliciously crafted web content may lead to an unexpected Safari crash.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "4.3",
  "pubDate": "2026-08-17T22:17:23.073Z",
  "pubdate": "2026-08-17T22:17:23.073Z",
  "executiveSummary": "An input validation vulnerability has been identified within Safari and web content processing components across multiple Apple operating system distributions, specifically affecting iOS, iPadOS, and macOS. The vulnerability arises from insufficient validation mechanisms when parsing or rendering maliciously crafted web content.\nSuccessful exploitation of this security flaw allows an unauthenticated remote threat actor to trigger an unexpected application crash, resulting in a localized denial of service condition for the Safari browser. The attack vector relies on forcing the affected browser to process specifically engineered web payloads designed to trigger parsing anomalies or memory boundary violations within the rendering engine.\nImpact is primarily restricted to availability degradation, specifically causing abrupt termination of the Safari application when interacting with hostile web resources. While remote code execution is not explicitly indicated by the vulnerability characteristics, denial of service conditions disrupt user operations and diminish system integrity. The risk is mitigated by updating the underlying operating systems to the patched versions.\nAffected products include iOS 18.7.10, iPadOS 18.7.10, iOS 26.6.1, iPadOS 26.6.1, and macOS Tahoe 26.6.2. Exploitation prerequisites require an attacker to successfully deliver maliciously crafted web content to the targeted client, typically through compromised websites, malicious advertisements, or adversarial links engineered to entice user interaction.",
  "technicalDetails": "The root cause of the vulnerability stems from inadequate input validation within the web content processing pipeline utilized by Safari. When the browser engine encounters complex, malformed, or maliciously crafted web content—such as structured data, markup, or embedded scripts—the lack of rigorous sanitization and boundary checks leads to improper state management or memory handling.\nThe vulnerable component resides within the parsing and rendering subsystems responsible for interpreting web payloads. The attack flow begins when a user navigates to an attacker-controlled web page or interacts with malicious web content embedded within a third-party application context. Upon retrieval, the affected parsing component attempts to process the anomalous data structures without enforcing strict schema validation or length constraints.\nAs the parsing engine processes the maliciously crafted elements, unexpected execution paths or unhandled exceptions are triggered due to malformed input values. This condition directly causes the Safari process to crash abruptly, terminating all active browser tabs and sessions associated with the instance. Network exposure is inherent to web browsing vectors, as victims interact with remote servers hosting the malicious payloads over standard web protocols (HTTP/HTTPS).\nAuthentication and privilege requirements for exploitation are minimal; the attacker requires no prior access, privileges, or valid credentials on the target host. The payload behavior is focused strictly on inducing instability within the application layer rather than establishing persistence or elevating privileges. Consequently, post-exploitation impact remains confined to application-level denial of service, without direct evidence of unauthorized data exfiltration or arbitrary code execution based on the provided vulnerability scope."
}