Overview
CVE-2025-54321 identifies a vulnerability in Ascertia SigningHub, specifically affecting versions up to 8.6.8. This vulnerability stems from a lack of proper rate limiting on the password reset function. As a result, an attacker with valid (or potentially even invalid) usernames can repeatedly trigger password reset requests, leading to an email bombing attack against targeted users.
Technical Details
The core issue lies in the absence of adequate rate limiting on the password reset endpoint. This allows an attacker to automate the process of requesting password reset emails for one or multiple users. By sending a high volume of these requests in a short period, the attacker can flood the user’s inbox, potentially burying legitimate emails and causing significant disruption. The vulnerability exploits the standard ‘forgot password’ functionality, a common feature in web applications. The absence of countermeasures, such as CAPTCHAs or IP address-based rate limiting, makes the attack trivially executable.
CVSS Analysis
Currently, a CVSS score has not been assigned to CVE-2025-54321. However, due to the potential impact of an email bombing attack, it is likely to receive a CVSS score within the Medium to High range once formally assessed. Factors influencing the score will include the ease of exploitation, the potential for denial of service (DoS), and the confidentiality impact (potential for missed important emails).
Possible Impact
The exploitation of this vulnerability can have several detrimental effects:
- Email Inbox Flooding: The primary impact is the flooding of targeted users’ inboxes with numerous password reset emails, making it difficult to find legitimate messages.
- Denial of Service (DoS): The flood of emails can overwhelm email servers, potentially impacting the overall availability of the email service.
- User Frustration and Confusion: Users may become frustrated and confused by the constant stream of password reset requests.
- Potential Security Risks: In some scenarios, email bombing could be used to distract users while other, more serious attacks are being carried out.
Mitigation and Patch Steps
To mitigate the risk posed by CVE-2025-54321, the following steps should be taken:
- Apply the Latest Patch: Upgrade to the latest version of Ascertia SigningHub that addresses this vulnerability. Contact Ascertia support for details on the patched version.
- Implement Rate Limiting: Implement robust rate limiting on the password reset endpoint. This should restrict the number of password reset requests that can be made from a single IP address or user account within a given timeframe.
- Implement CAPTCHA: Add CAPTCHA or similar challenge-response mechanisms to the password reset form to prevent automated requests.
- Monitor for Suspicious Activity: Monitor logs for unusual patterns of password reset requests.
References
GitHub: CVE-2025-54321 Proof of Concept
Ascertia Vulnerability Disclosure Policy
