CVE-2026-23497 identifies a stored cross-site scripting (XSS) vulnerability in the Frappe Learning Management System (LMS), versions 2.44.0 and earlier. The vulnerability stems from improper neutralization of input during web page generation, classified under CWE-79. Specifically, an attacker can craft an image filename containing malicious JavaScript code that, when uploaded and subsequently rendered on course or jobs pages, executes within the victim’s browser context. This stored XSS allows persistent script injection, which can lead to session hijacking, defacement, or redirection to malicious sites. The vulnerability does not require authentication or privileges to exploit but does require user interaction, such as viewing the affected page. The CVSS 4.0 vector (AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:U) reflects network attack vector, low complexity, no privileges, user interaction required, and low impact on confidentiality, integrity, and availability. No known exploits are currently reported in the wild, and no official patches have been linked yet. The root cause is insufficient sanitization and encoding of user-supplied filenames before rendering in HTML, allowing script injection. This vulnerability highlights the need for secure input handling and output encoding in web applications, especially those handling user-generated content like LMS platforms.

For European organizations using Frappe LMS, this vulnerability poses a risk primarily to confidentiality and integrity of user sessions and data viewed through the LMS interface. Attackers could exploit the stored XSS to execute malicious scripts in the browsers of educators, students, or administrators, potentially stealing session cookies, performing actions on behalf of users, or delivering further malware. While the direct impact on availability is negligible, the reputational damage and potential data leakage could be significant, especially for institutions handling sensitive educational data or personal information. The low CVSS score indicates limited severity, but the persistent nature of stored XSS means that once exploited, the malicious payload remains until removed. European educational institutions or companies relying on Frappe LMS for training could face targeted attacks aiming to disrupt learning activities or harvest credentials. The lack of known exploits reduces immediate risk, but proactive mitigation is advisable to prevent future exploitation.

To mitigate CVE-2026-23497, organizations should implement strict input validation and sanitization on all user-supplied filenames, ensuring that special characters and script tags are neutralized before storage or rendering. Employ robust output encoding techniques (e.g., HTML entity encoding) when displaying filenames in web pages to prevent script execution. Restrict allowable characters in image filenames to a safe subset (e.g., alphanumeric, underscores, hyphens) and enforce filename length limits. Regularly audit LMS content for suspicious filenames and remove or rename those containing potentially malicious payloads. Monitor web application logs for unusual activity related to file uploads or page views. Although no official patches are linked yet, organizations should track vendor advisories for updates and apply patches promptly once available. Additionally, implement Content Security Policy (CSP) headers to reduce the impact of XSS by restricting script sources. Educate users about the risks of clicking on suspicious links or content within the LMS. Finally, consider isolating LMS environments and limiting user privileges to reduce the attack surface.