CVE-2025-42615 Improper Restriction of Excessive Authentication Attempts vulnerability in CIRCL Vulnerability-Lookup
Attackers can brute-force 2FA OTP codes without lockout, leading to account takeover in Vulnerability-Lookup.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2025-42615?
CVE-2025-42615 is a high-severity vulnerability in CIRCL Vulnerability-Lookup, published on 8 Dec 2025. An attacker needs administrator access to exploit it, and only if a user opens a file or follows a link.
Official description
In affected versions, vulnerability-lookup did not track or limit failed One-Time Password (OTP) attempts during Two-Factor Authentication (2FA) verification. An attacker who already knew or guessed a valid username and password could submit an arbitrary number of OTP codes without causing the account to be locked or generating any specific alert for administrators.
This lack of rate-limiting and lockout on OTP failures significantly lowers the cost of online brute-force attacks against 2FA codes and increases the risk of successful account takeover, especially if OTP entropy is reduced (e.g. short numeric codes, user reuse, or predictable tokens). Additionally, administrators had no direct visibility into accounts experiencing repeated 2FA failures, making targeted attacks harder to detect and investigate.
The patch introduces a persistent failed_otp_attempts counter on user accounts, locks the user after 5 invalid OTP submissions, resets the counter on successful verification, and surfaces failed 2FA attempts in the admin user list. This enforces an account lockout policy for OTP brute-force attempts and improves monitoring capabilities for suspicious 2FA activity.This issue affects Vulnerability-Lookup: before 2.18.0.
Weakness: CWE-307
Which versions are affected by CVE-2025-42615?
How do I fix CVE-2025-42615?
No fix has been published for CVE-2025-42615 yet. Limit exposure of the affected software until one is available.
Is CVE-2025-42615 being exploited?
There is no known exploitation of CVE-2025-42615 in the wild and no public exploit code.
Sources
Also known as GHSA-w22j-qgr5-cw5m.