CVE-2019-5440

Severity: high (CVSS 8.1 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.6% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2019-05-28 · updated 2026-06-17
Weakness: CWE-338

Description

Use of cryptographically weak PRNG in the password recovery token generation of Revive Adserver < v4.2.1 causes a potential authentication bypass attack if an attacker exploits the password recovery functionality. In lib/OA/Dal/PasswordRecovery.php, the function generateRecoveryId() generates a password reset token that relies on the PHP uniqid function and consequently depends only on the current server time, which is often visible in an HTTP Date header.

Affected products

Revive Adserver: before 4.2.1 — fixed in 4.2.1

How to fix

Upgrade to a fixed version: Revive Adserver 4.2.1. Check the vendor advisory for mitigations.

References

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