CVE-2019-4540: IBM Security Directory Server

High severity, CVSS 7.5. EPSS: 0.8% chance of exploitation in the next 30 days.

IBM Security Directory Server 6.4.0 uses weaker than expected cryptographic algorithms that could allow an attacker to decrypt highly sensitive information. IBM X-Force ID: 165813.

Affected products

• IBM Security Directory Server: from 6.4.0.0, before 6.4.0.20 (fixed in 6.4.0.20)

Published 2020-02-04. Last modified 2026-06-17.