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

- Exploited (CISA KEV): no
- Published: 2023-10-16
- CVSS: 5.3 MEDIUM (v3.1)
- EPSS: 4.3% (91th percentile)

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

## Edge WAF coverage (claimed by vendors, not measured)

| Vendor | Status | First rule | Days after publication |
|---|---|---|---|
| Cloudflare | Blocks by default | 2025-08-04 | 658 |
| AWS | No public claim | — | — |
| Microsoft Azure | No public claim | — | — |
| Google Cloud | Before feed history | — | — |
| Fastly | Before feed history | — | — |
| F5 | No public claim | — | — |
| Akamai | No public source | — | — |
| OWASP CRS | No public claim | — | — |

### Cloudflare

- 2025-08-04 · new · rule bba3d37891a440fb8bc95b970cbd9abc · default Block
  > WordPress - Information Disclosure - CVE:CVE-2023-5561. Previous action: Log. New action: Block. This is a New Detection
  Source: https://developers.cloudflare.com/changelog/post/2025-08-04-waf-release/

## Our test (measured)

- OWASP Core Rule Set 4.25.0, paranoia level 1, anomaly threshold 5, default CRS settings: passed (0 of 2 requests blocked), template CVE-2023-5561, 2026-11-02
- OWASP Core Rule Set 4.25.0, paranoia level 2, anomaly threshold 5, default CRS settings: passed (0 of 2 requests blocked), template CVE-2023-5561, 2026-11-02

"No public claim" means no vendor statement names this CVE; "Before feed history" means the CVE is older than the vendor feed. In both cases generic rules may still block it.

HTML: https://cve.vigilbase.com/cve/CVE-2023-5561 · JSON: https://cve.vigilbase.com/api/v1/cves/CVE-2023-5561