IBM Security Directory Server 6.4.0 uses an inadequate account lockout setting that could allow a remote attacker to brute force account cr…

published 2019-10-02 7y ago modified 2026-06-17 4mo ago also EUVD-2019-14127

cvss: 7.5; version 3.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 2.2%; EPSS 2.2% chance of exploitation in 30 days, percentile 82%
public exploits: 0; none known

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.

Patch / fix

links 1

ibm.com/support/pages/node/1077045 advisory

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Exploit prediction

2.22% chance of exploitation in the next 30 days, higher than 82% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
CNA	3.0	7.5	CVSS:3.0/AC:L/UI:N/PR:N/A:N/I:N/AV:N/S:U/C:H/RC:C/RL:O/E:U
NVD	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
CNA	3.0	7.5	CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
NVD	2.0	5.0	AV:N/AC:L/Au:N/C:P/I:N/A:N

Affected products

IBM Security Directory Server

Classification

Weakness

CWE-307 Improper Restriction of Excessive Authentication Attempts

References

ibm.com /support/pages/node/1077045
patch, vendor-advisory
exchange.xforce.ibmcloud.com /vulnerabilities/165178
vdb-entry, vendor-advisory

Sources

CVE List CVE-2019-4520
NVD CVE-2019-4520

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