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Vulnerability DatabaseCVE-2021-4240
CVE-2021-4240:
PHP vulnerability analysis and mitigation
Overview
A vulnerability was identified in phpservermon affecting the generatePasswordResetToken function. The issue, tracked as CVE-2021-4240, was discovered in November 2022 and involves the use of a predictable algorithm (mt_rand) in the random number generator for password reset tokens (NVD).
Technical details
The vulnerability stems from the use of mt_rand() function in generating password reset tokens, which is considered cryptographically weak. The issue was addressed by replacing mt_rand with random_bytes for generating the password reset verification hash, and increasing the hash length from 40 to 64 characters using SHA-256 (GitHub Commit).
Impact
The use of a predictable random number generator could potentially allow attackers to predict password reset tokens, potentially leading to unauthorized account access through password reset functionality.
Mitigation and workarounds
The issue has been patched by implementing cryptographically secure random number generation using random_bytes() instead of mt_rand(), and upgrading the hash algorithm to SHA-256 with a 64-character output (GitHub Commit).
Additional resources
Source: This report was generated using AI
Related PHP vulnerabilities:
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