CVE-2025-31254 Overview
CVE-2025-31254 is a URL validation vulnerability in Apple Safari, iOS, and iPadOS. Processing maliciously crafted web content may lead to unexpected URL redirection. Apple addressed the flaw with improved URL validation in Safari 26, iOS 26, and iPadOS 26. The issue is categorized under [CWE-863] (Incorrect Authorization) and stems from insufficient enforcement of URL parsing rules within WebKit-based browsing contexts.
An attacker can use the flaw to redirect users to attacker-controlled destinations, enabling phishing, credential harvesting, and drive-by download scenarios. Exploitation requires only that the victim load a malicious web page, without additional user interaction beyond normal browsing.
Critical Impact
Attackers can trick Safari into redirecting users to arbitrary URLs, undermining trust boundaries used for phishing detection and same-origin controls.
Affected Products
- Apple Safari (versions prior to Safari 26)
- Apple iOS (versions prior to iOS 26)
- Apple iPadOS (versions prior to iPadOS 26)
Discovery Timeline
- 2025-09-15 - CVE-2025-31254 published to the National Vulnerability Database (NVD)
- 2025-09-15 - Apple releases fixes in Safari 26, iOS 26, and iPadOS 26 (Apple Support Article #125108, Apple Support Article #125113)
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-31254
Vulnerability Analysis
The vulnerability resides in Safari's URL validation logic. When Safari processes crafted web content, the browser fails to correctly validate URL components before honoring navigation or redirection requests. This leads to unexpected redirection to a destination that differs from what security policies or user expectations would allow.
The underlying weakness maps to [CWE-863] Incorrect Authorization. Safari authorizes a navigation action based on incomplete or inconsistent parsing of the target URL. An attacker abuses the mismatch between the parsed and effective URL to steer the browser to a location the origin should not be allowed to reach.
Exploitation does not yield direct code execution. Instead, attackers use the redirection primitive to defeat anti-phishing heuristics, chain into social engineering flows, or stage secondary exploits hosted at the attacker-controlled destination.
Root Cause
Apple's advisory states the issue was addressed with improved URL validation. The root cause is inadequate parsing and normalization of URL fields when Safari evaluates whether a navigation request should proceed. Edge cases in the URL specification create parser differentials that authorization checks fail to account for.
Attack Vector
The attack vector is network-based and requires the victim to visit a malicious page or a compromised site hosting attacker-controlled content. An authenticated web context with low privileges is sufficient. No local access or elevated permissions are required, and no user interaction beyond loading the page is needed.
Technical details are described in the Full Disclosure Mailing List Post and Apple's security advisories referenced above.
Detection Methods for CVE-2025-31254
Indicators of Compromise
- Web proxy or DNS logs showing user sessions redirected from legitimate domains to unexpected external hosts shortly after page load.
- Safari version telemetry reporting builds earlier than Safari 26, iOS 26, or iPadOS 26 in the fleet.
- Endpoint browsing history entries with rapid navigation chains through URL-shortener or lookalike domains.
Detection Strategies
- Inspect HTTP referrer chains and Location headers for anomalous cross-origin redirects that bypass typical navigation patterns.
- Correlate browser process telemetry with outbound DNS queries to newly registered or low-reputation domains.
- Deploy phishing-aware URL categorization at the network egress to flag redirection destinations that mismatch the initiating site's category.
Monitoring Recommendations
- Track Safari, iOS, and iPadOS version distribution across managed devices and alert on unpatched builds.
- Monitor mobile device management (MDM) compliance reports for delayed OS updates on iPhone and iPad endpoints.
- Ingest web gateway logs into a central analytics pipeline to identify clusters of users redirected to the same suspicious destinations.
How to Mitigate CVE-2025-31254
Immediate Actions Required
- Update all Apple devices to iOS 26, iPadOS 26, and Safari 26 or later without delay.
- Enforce OS update compliance through MDM policies for corporate iPhones, iPads, and macOS devices.
- Educate users about phishing risks that leverage unexpected redirections from otherwise trusted sites.
Patch Information
Apple has released fixes in Safari 26, iOS 26, and iPadOS 26. Refer to Apple Support Article #125108 and Apple Support Article #125113 for the official advisories and installation guidance. Apply the update on every affected endpoint and confirm the installed build matches or exceeds the patched version.
Workarounds
- Route Safari traffic through a secure web gateway that inspects and blocks redirects to low-reputation domains.
- Enable content and privacy restrictions on managed iOS and iPadOS devices to limit browsing to approved sites until patches are applied.
- Use an alternative, patched browser for high-risk workflows on devices that cannot immediately update to Safari 26.
# Verify iOS or iPadOS build via MDM query (example: Jamf)
# Devices returning versions below 26 must be updated.
jamf policy -event checkOSVersion
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
