CVE-2025-64239 identifies a Cross-Site Request Forgery (CSRF) vulnerability in the Yoav Farhi RTL Tester product, specifically affecting versions up to and including 1.2. CSRF vulnerabilities occur when a web application does not sufficiently verify that requests originate from legitimate users, allowing attackers to craft malicious web pages or links that cause authenticated users to unknowingly perform actions on the vulnerable application. In this case, the RTL Tester, a tool likely used for testing right-to-left language support in web applications, fails to implement adequate CSRF protections such as anti-CSRF tokens or origin checks. The CVSS 3.1 vector (AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N) indicates the attack can be performed remotely over the network with low attack complexity, requires no privileges, but does require user interaction (e.g., clicking a malicious link). The impact is limited to confidentiality loss, possibly leaking some user-specific data or session information, but does not affect data integrity or system availability. No known exploits are currently in the wild, and no patches have been published yet. The vulnerability was reserved in late October 2025 and published in mid-December 2025. Given the nature of the tool, the attack surface is primarily web-based interfaces used by developers or testers. Without proper CSRF defenses, attackers could leverage social engineering to induce users to execute unintended commands within the RTL Tester environment.

For European organizations, the primary impact of this vulnerability lies in the potential unauthorized execution of actions within the RTL Tester tool by tricking users into submitting forged requests. While the direct impact on confidentiality is low, any leakage of user-specific data or session information could facilitate further attacks or reconnaissance. Since the vulnerability does not affect integrity or availability, critical systems are unlikely to be disrupted directly. However, organizations relying on RTL Tester for web application testing, especially those developing multilingual or RTL language support websites, could face workflow disruptions or data exposure risks. Additionally, if the tool is integrated into broader development pipelines, attackers might leverage this vulnerability as a foothold to gather intelligence or pivot to other systems. The requirement for user interaction reduces the likelihood of widespread automated exploitation but does not eliminate targeted phishing or social engineering risks. Overall, the impact is moderate but warrants attention in environments where RTL Tester is actively used.

To mitigate CVE-2025-64239, organizations should implement several specific controls beyond generic advice: 1) Apply or develop patches that introduce anti-CSRF tokens in all state-changing requests within RTL Tester interfaces. 2) Enforce strict origin and referer header validation to ensure requests originate from trusted sources. 3) Restrict access to the RTL Tester tool to trusted internal networks or VPNs to reduce exposure to external attackers. 4) Educate users, especially developers and testers, about the risks of phishing and social engineering attacks that could exploit CSRF vulnerabilities. 5) Monitor web server logs for unusual or unexpected requests that could indicate attempted CSRF exploitation. 6) If possible, isolate the RTL Tester environment from production systems to limit potential lateral movement. 7) Implement Content Security Policy (CSP) headers to reduce the risk of malicious script execution that could facilitate CSRF attacks. 8) Regularly review and update security configurations of the testing environment to adhere to best practices for web application security. Since no official patch is currently available, these compensating controls are critical until a vendor fix is released.