CVE-2001-0660

CVE-2001-0660 is a medium-severity vulnerability in Microsoft Exchange Server with a CVSS 2.0 base score of 5.0. Its EPSS exploit-prediction score of 22% places it in the 97th percentile, indicating an elevated likelihood of exploitation.

Key facts

Description

Outlook Web Access (OWA) in Microsoft Exchange 5.5, SP4 and earlier, allows remote attackers to identify valid user email addresses by directly accessing a back-end function that processes the global address list (GAL).

Frequently asked questions

What is CVE-2001-0660?
Outlook Web Access (OWA) in Microsoft Exchange 5.5, SP4 and earlier, allows remote attackers to identify valid user email addresses by directly accessing a back-end function that processes the global address list (GAL).
How severe is CVE-2001-0660?
CVE-2001-0660 has a CVSS 2.0 base score of 5.0, rated medium severity.
Is CVE-2001-0660 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 22% (97th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2001-0660?
CVE-2001-0660 affects Microsoft Exchange Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2001-0660?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2001-0660 published?
CVE-2001-0660 was published on 2001-10-30 and last updated on 2026-06-16.

References

Affected products (1)

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