CVE-2025-50736 identifies an open redirect vulnerability in Byaidu PDFMathTranslate version 1.9.9. The vulnerability resides in the /gradio_api endpoint where the file parameter is improperly validated, allowing attackers to craft URLs that redirect users to arbitrary external websites. This flaw can be exploited by attackers to conduct phishing campaigns by luring users to malicious sites that appear to originate from a trusted application. Additionally, it can be used to bypass security filters that rely on URL reputation or domain whitelisting by redirecting through the vulnerable application’s domain. The vulnerability does not require any privileges (PR:N) but does require user interaction (UI:R) to follow the malicious link. The CVSS 3.1 vector (AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N) indicates network attack vector, low attack complexity, no privileges required, user interaction needed, scope changed due to redirection, and low impact on confidentiality and integrity with no impact on availability. No patches or known exploits are currently available, but the vulnerability is publicly disclosed and should be addressed promptly. The CWE-601 classification confirms this is a classic open redirect issue. Organizations using Byaidu PDFMathTranslate should review their usage of the /gradio_api endpoint and implement input validation and output encoding to prevent malicious redirects.

For European organizations, the primary impact of this vulnerability is the increased risk of successful phishing attacks and social engineering campaigns. Attackers can exploit the trust users place in the legitimate Byaidu domain to redirect them to malicious websites designed to steal credentials, distribute malware, or harvest sensitive information. This can lead to compromised user accounts, data breaches, and potential lateral movement within networks if credentials are reused. The vulnerability could also undermine security controls that rely on URL filtering or domain reputation, reducing the effectiveness of existing defenses. While the direct impact on system confidentiality and integrity is low, the indirect consequences through phishing could be significant. Organizations in sectors with high regulatory requirements for data protection, such as finance, healthcare, and government, may face compliance risks if phishing leads to data exposure. The lack of known exploits in the wild reduces immediate risk but does not eliminate the threat, especially as attackers often weaponize such vulnerabilities rapidly after disclosure.

To mitigate CVE-2025-50736, organizations should implement strict validation and sanitization of the file parameter in the /gradio_api endpoint to ensure that only legitimate, internal URLs are accepted. Employing an allowlist approach for redirect destinations is recommended to prevent arbitrary external redirects. Additionally, output encoding should be applied to URLs to prevent injection of malicious payloads. Web application firewalls (WAFs) can be configured to detect and block suspicious redirect patterns targeting this endpoint. User education campaigns should emphasize caution when clicking on links, especially those received via email or messaging platforms. Monitoring for unusual redirect activity and anomalous URL requests can help detect exploitation attempts. If possible, update or patch the Byaidu PDFMathTranslate software once a fix is released. In the interim, consider disabling or restricting access to the vulnerable endpoint if it is not essential for business operations. Finally, integrate URL scanning and sandboxing solutions to analyze links before users interact with them.