CVE-2026-64964 in ATutor
Summary
by MITRE • 08/20/2026
ATutor generates predictable email confirmation tokens due to the use of insufficiently random values in the account confirmation functionality. Due to the use of predictable values related to user registration, an attacker who knows or can predict these values can guess valid account activation tokens. This allows an attacker to activate an unconfirmed account without access to the victim's email inbox. Product is no longer actively supported and the vulnerabilities have not been fixed. Only version 2.2.4 was tested and confirmed as vulnerable, other versions were not tested but might also be vulnerable.
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Analysis
by VulDB Data Team • 08/20/2026
The vulnerability in ATutor stems from a fundamental flaw in its account confirmation mechanism, specifically categorized under CWE-330: Use of Insufficiently Random Values. When users register for an account on the platform, they are required to confirm their email address via a unique token sent to them. This process is designed as a security control to ensure that only legitimate owners of the provided email addresses can activate accounts and gain access to system features. However, ATutor generates these confirmation tokens using insufficiently random values derived from user registration data or other predictable inputs rather than cryptographically secure pseudo-random number generators. As a result, the generated tokens lack entropy and are susceptible to prediction by an attacker who has knowledge of the input parameters used during token generation.
From an operational perspective, this weakness allows for account takeover without requiring access to the victim's email inbox. An attacker can exploit this flaw by guessing or brute-forcing valid activation tokens if they possess sufficient information about the user registration process, such as usernames, timestamps, or other predictable identifiers associated with the account creation event. Once a valid token is guessed, the attacker gains immediate control over the unconfirmed account. This bypasses one of the primary defenses against unauthorized access and can lead to further exploitation depending on the privileges assigned to new accounts within ATutor. The impact includes potential data exposure, misuse of platform resources, or use as a foothold for more advanced attacks if additional vulnerabilities exist in authenticated sections of the application.
This type of vulnerability aligns with MITRE ATT&CK technique T1078: Valid Accounts, where attackers leverage legitimate credentials to gain access to systems and networks. In this case, although no password is stolen initially, the ability to activate an account effectively grants valid login capabilities without proper authentication through email verification. This undermines trust in identity management processes and weakens overall system integrity. Organizations relying on ATutor for educational or administrative purposes must recognize that such flaws compromise both confidentiality and availability principles of information security.
Given that ATutor is no longer actively supported, there are no official patches available to remediate this issue directly within the software itself. Therefore, mitigation strategies must focus on compensating controls and architectural adjustments. One effective approach involves implementing additional layers of authentication beyond email confirmation, such as multi-factor authentication mechanisms for all user roles. Additionally, deploying web application firewalls with rules capable of detecting anomalous registration patterns or token usage may help mitigate exploitation attempts in real time.
Administrators should also consider isolating ATutor instances behind reverse proxies that enforce rate limiting on account creation and activation endpoints to reduce the feasibility of brute-force attacks against predictable tokens. If possible, migrating away from unsupported software like older versions of ATutor toward actively maintained platforms with robust security practices is strongly recommended. Until such migration occurs or alternative mitigations are implemented, organizations should treat any exposed instances as high-risk environments requiring continuous monitoring and strict access controls to minimize potential damage stemming from this vulnerability.