CVE-2023-5561: WordPress < 6.3.2 - Unauthenticated Post Author Email Disclosure

Severity: medium (CVSS 5.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 4.3% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2023-10-16 · updated 2026-06-17

Description

WordPress does not properly restrict which user fields are searchable via the REST API, allowing unauthenticated attackers to discern the email addresses of users who have published public posts on an affected website via an Oracle style attack

Affected products

WordPress: from 4.7 before 4.7.27; from 4.8 before 4.8.23; from 4.9 before 4.9.24; from 5.0 before 5.0.20; from 5.1 before 5.1.17; from 5.2 before 5.2.19 — fixed in 4.7.27, 4.8.23, 4.9.24, 5.0.20, 5.1.17, 5.2.19

How to fix

Upgrade to a fixed version: WordPress 4.7.27, 4.8.23, 4.9.24, 5.0.20. Check the vendor advisory for mitigations.

References

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