CVE-2025-56526 identifies a cross-site scripting (XSS) vulnerability in Kotaemon version 0.11.0, a software component that processes PDF files. The vulnerability arises from improper sanitization of input embedded within crafted PDF documents, enabling attackers to inject malicious scripts. When a user opens a maliciously crafted PDF, the embedded script can execute arbitrary code within the context of the application, potentially compromising confidentiality and integrity of data handled by Kotaemon. The vulnerability has a CVSS v3.1 base score of 6.1, reflecting network attack vector (AV:N), low attack complexity (AC:L), no privileges required (PR:N), but requiring user interaction (UI:R). The scope is changed (S:C), indicating that the vulnerability affects components beyond the initially vulnerable component. The impact on confidentiality and integrity is low (C:L, I:L), with no impact on availability (A:N). No patches or fixes have been released at the time of publication, and no known exploits are reported in the wild. The vulnerability is categorized under CWE-79, which is a common weakness related to improper neutralization of input leading to XSS attacks. This vulnerability can be exploited by attackers who craft malicious PDF files and trick users into opening them, leading to script execution within the vulnerable application environment. The lack of required privileges lowers the barrier for exploitation, but the need for user interaction reduces the likelihood of widespread automated exploitation. The vulnerability is particularly relevant for environments where Kotaemon is used to process or display PDF files, especially if those files originate from untrusted or external sources.

For European organizations, this vulnerability poses a moderate risk primarily to confidentiality and integrity of data processed by Kotaemon 0.11.0. Attackers could leverage this XSS flaw to execute arbitrary scripts, potentially leading to data leakage, session hijacking, or unauthorized actions within the application context. Sectors heavily reliant on PDF processing, such as legal, financial, and governmental institutions, may face increased exposure. The requirement for user interaction limits automated mass exploitation but does not eliminate targeted phishing or social engineering attacks. Since availability is not impacted, operational disruption is unlikely. However, the compromise of sensitive information or unauthorized code execution could lead to reputational damage, regulatory non-compliance (e.g., GDPR), and financial losses. The absence of patches necessitates immediate risk management and mitigation to prevent exploitation. Organizations using Kotaemon in critical workflows should prioritize assessment and containment to reduce attack surface exposure.

1. Restrict and validate all PDF inputs: Implement strict whitelisting and validation of PDF sources to prevent untrusted or suspicious files from being processed by Kotaemon. 2. Employ sandboxing: Run Kotaemon in a sandboxed environment or container to limit the impact of any successful code execution. 3. Enhance input sanitization: If possible, apply additional input filtering or sanitization layers before PDF processing to neutralize embedded scripts. 4. User awareness training: Educate users about the risks of opening PDFs from unknown or untrusted sources to reduce the likelihood of user interaction exploitation. 5. Monitor logs and network traffic: Set up detection mechanisms for anomalous behavior or suspicious script execution patterns related to Kotaemon PDF processing. 6. Stay updated: Monitor vendor announcements for patches or updates addressing this vulnerability and apply them promptly once available. 7. Consider alternative PDF processing tools: If feasible, evaluate replacing Kotaemon with more secure or actively maintained solutions until a fix is released. 8. Implement Content Security Policy (CSP): If Kotaemon is used in a web context, configure CSP headers to restrict script execution and mitigate XSS impact.