How severe is CVE-2006-4403?

CVE-2006-4403 has a CVSS 2.0 base score of 4.0, rated medium severity.

Is CVE-2006-4403 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (88th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2006-4403?

CVE-2006-4403 affects Apple Mac Os X. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2006-4403?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2006-4403 published?

CVE-2006-4403 was published on 2006-11-30 and last updated on 2026-06-16.

CVE-2006-4403

CVE-2006-4403 is a medium-severity vulnerability in Apple Mac Os X with a CVSS 2.0 base score of 4.0. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Medium (CVSS 2.0 base score 4.0)
EPSS exploit prediction: 4% (88th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Apple Mac Os X
Published: 2006-11-30
Last modified: 2026-06-16

Description

The FTP server in Apple Mac OS X 10.4.8 and earlier, when FTP Access is enabled, will crash when a login failure occurs with a valid user name, which allows remote attackers to cause a denial of service (crash) and enumerate valid usernames.

Frequently asked questions

What is CVE-2006-4403?: The FTP server in Apple Mac OS X 10.4.8 and earlier, when FTP Access is enabled, will crash when a login failure occurs with a valid user name, which allows remote attackers to cause a denial of service (crash) and enumerate valid usernames.
How severe is CVE-2006-4403?: CVE-2006-4403 has a CVSS 2.0 base score of 4.0, rated medium severity.
Is CVE-2006-4403 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (88th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2006-4403?: CVE-2006-4403 affects Apple Mac Os X. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2006-4403?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2006-4403 published?: CVE-2006-4403 was published on 2006-11-30 and last updated on 2026-06-16.

References

Affected products (1)

cpe:2.3:o:apple:mac_os_x:*:*:*:*:*:*:*:*

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