CVE-2026-73491
Description
A flaw was found in Loofah. The Loofah::HTML5::Scrub.allowed_uri? function fails to properly detect javascript: Uniform Resource Identifiers (URIs) when their scheme is split or prefixed with HTML5 named whitespace character references, such as 	 or 
. This vulnerability allows a remote attacker to craft a malicious URI that, when processed by affected callers, is incorrectly deemed safe. Consequently, a web browser will decode and execute the embedded JavaScript code, leading to Cross-Site Scripting (XSS) and potential arbitrary code execution in the user's browser context.
Statement
Red Hat Product Security has determined that this vulnerability does not affect any currently supported Red Hat product. This assessment may evolve based on further analysis and discovery. For more information about this vulnerability and the products it affects, please see the linked references.
Understanding the Weakness (CWE)
Other
Technical Impact: Varies by Context
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