How severe is CVE-2019-5440?

CVE-2019-5440 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2019-5440 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-5440?

CVE-2019-5440 affects Revive-adserver Revive Adserver. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2019-5440?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2019-5440 published?

CVE-2019-5440 was published on 2019-05-28 and last updated on 2026-06-17.

CVE-2019-5440

CVE-2019-5440 is a high-severity vulnerability in Revive-adserver Revive Adserver with a CVSS 3.x base score of 8.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-338.

Key facts

Severity: High (CVSS 3.x base score 8.1)
CVSS v2: 6.8
EPSS exploit prediction: 2% (73rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-338
Affected product: Revive-adserver Revive Adserver
Published: 2019-05-28
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2019-5440?: 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.
How severe is CVE-2019-5440?: CVE-2019-5440 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2019-5440 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-5440?: CVE-2019-5440 affects Revive-adserver Revive Adserver. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2019-5440?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2019-5440 published?: CVE-2019-5440 was published on 2019-05-28 and last updated on 2026-06-17.

References

https://hackerone.com/reports/576504

Affected products (1)

cpe:2.3:a:revive-adserver:revive_adserver:*:*:*:*:*:*:*:*

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