CVE-2025-8591
Summary
by MITRE • 07/06/2026
The software accepts user-supplied input via a URL parameter without adequate output encoding before reflecting it back to the user's browser. This condition allows an attacker to inject malicious script content into pages served by the application.
By leveraging this weakness, an attacker can cause the user's browser to redirect to a malicious website, modify the UI of the webpage, or retrieve information from the browser. However, the impact is mitigated by the use of httpOnly flags on session-related cookies, preventing session hijacking.
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Analysis
by VulDB Data Team • 07/06/2026
This vulnerability represents a classic cross-site scripting flaw that exists when applications fail to properly sanitize and encode user input before incorporating it into web responses. The weakness occurs specifically within URL parameter handling where the application directly reflects user-supplied data without appropriate output encoding mechanisms. According to CWE-79, this classification encompasses the injection of malicious scripts into web pages viewed by other users, making it a fundamental security concern in web application development.
The technical exploitation of this vulnerability enables attackers to execute malicious JavaScript code within the context of a victim's browser session through manipulated URL parameters. This allows for various harmful activities including but not limited to unauthorized redirections to malicious domains, manipulation of webpage user interfaces to deceive users, and potential data exfiltration from the browser environment. The reflected nature of this attack means that the malicious payload is immediately executed upon page load when the vulnerable parameter is processed by the web application.
From an operational impact perspective, this vulnerability creates significant risks for both application integrity and user security. While the presence of httpOnly flags on session cookies provides some protection against session hijacking attacks, it does not prevent other forms of exploitation such as credential theft through DOM-based XSS, phishing attacks, or data manipulation within the application interface. The attack surface extends beyond simple session compromise to include potential privilege escalation and information disclosure scenarios that could affect multiple users depending on the application's access control mechanisms.
Security practitioners should implement comprehensive input validation and output encoding strategies to address this vulnerability. The recommended mitigation approach includes implementing strict input sanitization routines that remove or encode potentially dangerous characters before processing user data, utilizing proper output encoding techniques such as HTML entity encoding for web content, and implementing Content Security Policy headers to restrict script execution. Additionally, organizations should conduct regular security testing including automated scanning and manual penetration testing to identify and remediate similar vulnerabilities across their application portfolio. This vulnerability aligns with ATT&CK technique T1059.007 for script injection and demonstrates the importance of following secure coding practices as outlined in OWASP Top Ten Project recommendations.