CVE-2016-0125 in Edge
Summary
by MITRE
Microsoft Edge mishandles the Referer policy, which allows remote attackers to obtain sensitive browser-history and request information via a crafted HTTPS web site, aka "Microsoft Edge Information Disclosure Vulnerability."
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Analysis
by VulDB Data Team • 07/09/2022
The vulnerability identified as CVE-2016-0125 represents a significant information disclosure flaw in Microsoft Edge browser that stems from improper handling of the Referer policy. This weakness specifically affects the browser's ability to manage cross-origin requests and maintain proper privacy boundaries between different web origins. The vulnerability manifests when a malicious HTTPS website attempts to exploit the browser's Referer header processing mechanism to extract sensitive information about the user's browsing history and request patterns. The flaw exists within the browser's security model where it fails to adequately sanitize or restrict the information transmitted in Referer headers when navigating between different security contexts.
The technical implementation of this vulnerability exploits the fundamental principle that browsers should maintain strict separation between different origins to prevent information leakage. When Microsoft Edge processes requests between secure (HTTPS) origins, it incorrectly propagates sensitive Referer information that contains details about the user's navigation history and the specific URLs being accessed. This occurs because the browser's Referer policy implementation does not properly account for the security implications of including detailed path information, query parameters, or even fragment identifiers in the Referer header when transitioning from one secure context to another. The flaw is particularly dangerous because it can be triggered through a crafted HTTPS website that specifically designs its requests to extract this sensitive information from the browser's internal state.
The operational impact of this vulnerability extends beyond simple information disclosure to potentially enable sophisticated tracking and profiling attacks against users. Attackers can construct malicious web pages that leverage the improper Referer handling to reconstruct user browsing patterns, identify sensitive websites visited, and even determine the nature of specific requests made to various services. This information can be used for targeted advertising, social engineering attacks, or more serious privacy violations that compromise user anonymity. The vulnerability affects users who may inadvertently visit compromised websites while using Microsoft Edge, making it particularly concerning for general web browsing scenarios where users encounter untrusted content. The attack vector requires only a malicious website to be loaded in the browser, making it difficult for users to defend against without proper security measures or browser updates.
Mitigation strategies for CVE-2016-0125 should focus on both immediate remediation and long-term security hardening approaches. Microsoft addressed this vulnerability through security updates that modified the Referer policy implementation to prevent excessive information disclosure in cross-origin requests. Organizations should ensure all Microsoft Edge installations are updated to versions that contain the appropriate patches, typically released as part of regular security updates. Browser security configurations should be reviewed to implement stricter Referer policies that limit information exposure, particularly when transitioning between secure contexts. The vulnerability aligns with CWE-200, which addresses "Information Exposure," and can be categorized under ATT&CK technique T1566 for credential access through social engineering, as the information leakage could enable more sophisticated attacks. Users should also implement additional security measures such as browser extensions that provide enhanced privacy controls and regularly monitor for updates to their browser software to maintain protection against similar vulnerabilities that may arise from improper handling of web security policies and cross-origin resource management.