The vulnerability identified as CVE-2025-62709 affects the ClipBucket v5 open source video sharing platform, specifically versions from 5.5.2 up to but not including 5.5.2#162. The root cause is a weak password recovery mechanism stemming from the dynamic construction of the server URL in the password reset process. When the configuration parameter base_url is not set, the application uses the incoming HTTP Host header to build URLs for password reset emails. Since the Host header is client-controlled, an attacker can supply an arbitrary domain name. Consequently, password reset links sent to users contain URLs pointing to the attacker’s domain. If a victim clicks such a link and enters their activation code on the attacker-controlled site, the attacker captures this code and can use it to reset the victim’s password, thereby taking over the account. This attack vector compromises both confidentiality and integrity of user accounts. The vulnerability does not require prior authentication but does require user interaction (clicking the malicious link and submitting the code). The vulnerability is classified under CWE-640, which relates to weak password recovery mechanisms. The issue was addressed and patched in ClipBucket version 5.5.2#162. The CVSS v3.1 base score is 6.8, reflecting medium severity with network attack vector, high impact on confidentiality and integrity, and requiring user interaction with high attack complexity.

For European organizations using vulnerable versions of ClipBucket v5, this vulnerability poses a significant risk to user account security. Attackers can hijack user accounts by intercepting password reset tokens, potentially gaining unauthorized access to sensitive video content, user data, and administrative functions if privileged accounts are compromised. This can lead to data breaches, reputational damage, and regulatory non-compliance under GDPR due to unauthorized access to personal data. Organizations operating public-facing video sharing platforms are particularly at risk, as attackers can craft phishing campaigns with malicious password reset links. The attack requires user interaction, so social engineering is a key enabler. The compromise of user accounts could also facilitate further lateral movement or privilege escalation within the organization’s infrastructure. Although no known exploits are currently reported in the wild, the medium severity and ease of exploitation via phishing warrant urgent remediation.

1. Immediately upgrade ClipBucket installations to version 5.5.2#162 or later, where the vulnerability is patched. 2. Explicitly configure the base_url parameter in ClipBucket’s configuration to a fixed, trusted domain to prevent dynamic URL construction from the Host header. 3. Implement email link validation and monitoring to detect and block password reset emails containing unexpected domains. 4. Educate users to verify URLs in password reset emails and be cautious of unsolicited password reset requests. 5. Employ multi-factor authentication (MFA) for user accounts to reduce the impact of compromised passwords. 6. Monitor logs for suspicious password reset requests and unusual account activities. 7. Consider implementing web application firewalls (WAF) rules to detect and block requests with suspicious Host headers. 8. Regularly audit and test the password recovery workflow to ensure no similar weaknesses exist.