CVE-2020-9405 in Online Weather
Summary
by MITRE
IBL Online Weather before 4.3.5a allows unauthenticated reflected XSS via the redirect page.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 05/11/2025
The vulnerability identified as CVE-2020-9405 affects IBL Online Weather versions prior to 4.3.5a and represents a critical security flaw enabling unauthenticated reflected cross-site scripting attacks. This vulnerability exists within the application's redirect page functionality, where user-supplied input is not properly sanitized or validated before being returned to the browser. The reflected nature of this vulnerability means that malicious actors can craft specially designed URLs that, when clicked by unsuspecting users, will execute malicious JavaScript code within the victim's browser context.
The technical implementation of this flaw stems from inadequate input validation and output encoding practices within the redirect handling mechanism. When the application processes redirect parameters without proper sanitization, it fails to neutralize potentially malicious script content that could be embedded within the redirect URL. This creates an environment where attackers can inject malicious payloads that will execute in the context of the victim's browser session, effectively bypassing the normal security boundaries that protect against such attacks. The vulnerability aligns with CWE-79, which specifically addresses cross-site scripting flaws, and demonstrates poor input validation practices that violate fundamental web application security principles.
The operational impact of this vulnerability is significant as it allows attackers to perform a wide range of malicious activities without requiring authentication or user interaction beyond clicking a malicious link. An attacker could potentially steal session cookies, perform unauthorized actions on behalf of users, redirect victims to malicious sites, or even install malware through the executed JavaScript code. The unauthenticated nature of this vulnerability means that any user visiting a crafted link could be compromised, making it particularly dangerous for applications that serve a broad user base. This vulnerability could be exploited as part of larger attack campaigns, potentially enabling privilege escalation or data exfiltration attacks that leverage the victim's authenticated session.
Mitigation strategies for this vulnerability should focus on implementing comprehensive input validation and output encoding mechanisms throughout the application's redirect functionality. The most effective approach involves sanitizing all user-supplied input parameters before they are processed or returned to the browser, ensuring that any potentially malicious content is neutralized through proper encoding or filtering techniques. Additionally, implementing proper HTTP headers such as Content Security Policy can provide an additional layer of protection against reflected XSS attacks. The vendor has addressed this issue in version 4.3.5a through proper input validation and output sanitization measures, which aligns with ATT&CK technique T1566.001 for initial access through spearphishing attachments or links, and demonstrates the importance of maintaining up-to-date security patches in preventing exploitation of known vulnerabilities. Organizations should implement regular security assessments and maintain strict patch management procedures to prevent similar vulnerabilities from being exploited in their environments.