CVE-2025-51629 is a cross-site scripting (XSS) vulnerability identified in the PdfViewer component of the Agenzia Impresa Eccobook software version 2.81.1. This vulnerability arises from improper sanitization or validation of user-supplied input in the 'Temp' parameter, which allows an attacker to inject crafted malicious scripts or HTML content. When a victim accesses the vulnerable component with the malicious payload, the injected script executes in the context of the victim's browser. This can lead to session hijacking, credential theft, unauthorized actions on behalf of the user, or delivery of further malware. The vulnerability specifically targets the PdfViewer component, which is likely used to render or display PDF documents within the application interface. No CVSS score has been assigned yet, and there are no known exploits in the wild at the time of publication. The lack of patch links suggests that a fix may not yet be available, increasing the urgency for organizations to implement mitigations. Since XSS vulnerabilities require user interaction (victims must access the maliciously crafted URL or content), the attack vector is typically through phishing or malicious links embedded in documents or web pages. However, the impact on confidentiality and integrity can be significant, especially if the application handles sensitive business or personal data. The vulnerability affects version 2.81.1 of Agenzia Impresa Eccobook, a software product whose market penetration and usage details are not widely documented but appears to be a business-oriented application, possibly with a European user base given the Italian naming convention.

For European organizations using Agenzia Impresa Eccobook 2.81.1, this XSS vulnerability poses a risk of client-side attacks that can compromise user sessions and data confidentiality. Attackers could leverage this vulnerability to steal authentication tokens, perform actions on behalf of users, or deliver secondary payloads such as ransomware or spyware. This is particularly concerning for organizations handling sensitive financial, legal, or personal data, as unauthorized access or data leakage could lead to regulatory penalties under GDPR and damage to reputation. The exploitation of this vulnerability could also facilitate lateral movement within an organization's network if attackers gain access to privileged accounts. Since the vulnerability is in a PDF viewer component, users who frequently interact with PDF documents through this software are at higher risk. The absence of known exploits currently reduces immediate risk but does not eliminate the threat, as attackers often develop exploits rapidly once vulnerabilities are disclosed. European organizations should be vigilant, especially those in sectors such as finance, government, and legal services, where document handling is critical and security requirements are stringent.

1. Immediate mitigation should include restricting or sanitizing user input to the 'Temp' parameter at the application or web server level to prevent injection of malicious scripts. 2. Implement Content Security Policy (CSP) headers to limit the execution of unauthorized scripts in the browser context. 3. Educate users about phishing risks and the dangers of clicking on untrusted links or opening suspicious documents. 4. Monitor web application logs for unusual or suspicious requests targeting the PdfViewer component, especially those containing script tags or encoded payloads in the 'Temp' parameter. 5. If possible, disable or restrict the use of the vulnerable PdfViewer component until a patch or update is released by the vendor. 6. Engage with the vendor to obtain timelines for patches or updates and apply them promptly once available. 7. Employ web application firewalls (WAFs) with rules designed to detect and block XSS attack patterns targeting the application. 8. Conduct regular security assessments and penetration testing focused on client-side vulnerabilities to identify and remediate similar issues proactively.