CVE-2025-51741 is a denial of service vulnerability identified in Veal98 Echo Open-Source Community System versions 2.2 through 2.3. The flaw exists in the /sendEmailCodeForResetPwd API endpoint, which is designed to send email verification codes for password resets. Due to insufficient access controls, an unauthenticated attacker can repeatedly invoke this endpoint to send verification emails to arbitrary users without restriction. This can overwhelm the server's email sending capabilities, potentially causing resource exhaustion and service degradation or outage. Additionally, the targeted users may receive excessive unsolicited emails, leading to user disruption and possible reputational damage. The vulnerability is categorized under CWE-400 (Uncontrolled Resource Consumption), indicating that the root cause is a lack of rate limiting or abuse prevention mechanisms. The CVSS v3.1 base score is 7.5, reflecting a high impact on availability with no impact on confidentiality or integrity. Exploitation requires no privileges or user interaction, increasing the risk of automated attacks. Although no known exploits have been reported in the wild, the ease of exploitation and potential impact warrant immediate attention. No patches have been linked yet, so organizations must apply compensating controls to mitigate risk.

For European organizations, this vulnerability poses a significant risk of service disruption, especially for community platforms or services relying on Veal98 Echo for user management and password resets. Denial of service conditions can degrade user experience, reduce trust, and interrupt critical communications. The flood of verification emails can also lead to email provider blacklisting or increased operational costs due to excessive email traffic. Organizations with large user bases are particularly vulnerable to large-scale abuse. The impact extends beyond the affected server to downstream users who may be spammed or confused by unsolicited emails. This can also have regulatory implications under GDPR if user experience or service availability is compromised. Furthermore, organizations in sectors where community engagement platforms are critical (e.g., education, local government, non-profits) may face operational challenges. The lack of authentication requirements and ease of exploitation increase the likelihood of automated attacks originating from anywhere, including within Europe.

To mitigate this vulnerability, European organizations should implement strict rate limiting on the /sendEmailCodeForResetPwd endpoint to prevent abuse by automated scripts. Introducing CAPTCHA challenges or other bot-detection mechanisms can reduce automated exploitation. If possible, require authentication or multi-factor verification before allowing email code requests. Monitoring email sending logs for unusual spikes or patterns can help detect ongoing abuse early. Organizations should also consider temporarily disabling the vulnerable endpoint if feasible until a patch is available. Collaborating with email service providers to handle potential spam issues proactively is advisable. Additionally, updating to a patched version once released is critical. Network-level protections such as web application firewalls (WAFs) can be configured to block suspicious traffic targeting this endpoint. Finally, educating users about potential phishing or spam risks related to unsolicited password reset emails can reduce downstream impact.