How severe is CVE-2019-4520?

CVE-2019-4520 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2019-4520 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (81st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-4520?

CVE-2019-4520 affects Ibm Security Directory Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2019-4520?

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-2019-4520 published?

CVE-2019-4520 was published on 2019-10-02 and last updated on 2026-06-17.

CVE-2019-4520

CVE-2019-4520 is a high-severity vulnerability in Ibm Security Directory Server with a CVSS 3.x base score of 7.5. 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-307.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 2% (81st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-307
Affected product: Ibm Security Directory Server
Published: 2019-10-02
Last modified: 2026-06-17

Description

IBM Security Directory Server 6.4.0 uses an inadequate account lockout setting that could allow a remote attacker to brute force account credentials. IBM X-Force ID: 165178.

Frequently asked questions

What is CVE-2019-4520?: IBM Security Directory Server 6.4.0 uses an inadequate account lockout setting that could allow a remote attacker to brute force account credentials. IBM X-Force ID: 165178.
How severe is CVE-2019-4520?: CVE-2019-4520 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2019-4520 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (81st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-4520?: CVE-2019-4520 affects Ibm Security Directory Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2019-4520?: 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-2019-4520 published?: CVE-2019-4520 was published on 2019-10-02 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:ibm:security_directory_server:6.4.0:*:*:*:*:*:*:*

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