CVE-2009-2335: WordPress and WordPress MU before 2.8.1 exhibit different behavior for a failed login attempt depending on whether the user account exists, which allows remote attackers to enumerate valid usernames.

medium Affects WordPress core. Feed 2026.10.29.1, updated 2026-10-28; published 2009-07-10; advisory modified 2026-06-16.

WordPress and WordPress MU before 2.8.1 exhibit different behavior for a failed login attempt depending on whether the user account exists, which allows remote attackers to enumerate valid usernames.

Package: WordPress core WordPress
Affected versions: <2.8.1
Fixed in: 2.8.1
Severity: medium CVSS 5.0
Exploitation: not on CISA KEV · EPSS 85% (99.7th percentile)
Published: 2009-07-10
Source: nvd

References

CWE-16

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