The vulnerability, cataloged as CVE-2019-5418, affects the Action View component of Rails and enables attackers to exploit specially crafted accept headers in combination with render file: calls to access arbitrary files on target servers. CVE-2019-5418 in Ruby on Rails allows attackers to access arbitrary server files through exploited Accept headers and render file calls. This security flaw was added to CISA’s Known Exploited Vulnerabilities (KEV) catalog on July 7, 2025, with organizations given until July 28, 2025, to implement necessary mitigations or discontinue use of affected products. Enables unauthorized access to sensitive system files, configurations, and credentials via malicious HTTP Accept headers with directory traversal sequences. The vulnerability occurs when applications use the render file: method in combination with user-controlled input, particularly through manipulated HTTP Accept headers. Organizations must also ensure that applications follow the principle of least privilege, restricting file system access to only necessary directories and implementing comprehensive logging to detect potential exploitation attempts. The exploitation mechanism involves constructing specially crafted HTTP requests with manipulated Accept headers that bypass Rails’ intended security controls. Organizations should implement strict input validation for any file rendering operations and avoid using render file: with user-controlled parameters.
This Cyber News was published on cybersecuritynews.com. Publication date: Tue, 08 Jul 2025 16:05:11 +0000