wpDiscuz before 7.6.47 contains a missing rate limiting vulnerability that allows unauthenticated attackers to subscribe arbitrary email addresses to post notifications by sending POST requests to the wpdAddSubscription handler in class.WpdiscuzHelperAjax.php. Attackers can exploit LIKE wildcard characters in the subscription query to match multiple email addresses and generate unwanted notification emails to victim accounts.
Conclusion & alert: CVE-2026-22216 is rated Low Risk (35/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.07%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-04-14 | 0.04% | 0.07% | +0.03% |
| 2 | 2026-03-13 | — | 0.04% | — |
Full EPSS history (2 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 6.9 | 4.0 | MEDIUM |
|
— | — | [email protected] |
| 6.5 | 3.1 | MEDIUM |
|
3.9 | 2.5 | [email protected] |
| 5.3 | 3.1 | MEDIUM |
|
3.9 | 1.4 | [email protected] |
| URL | Tags |
|---|---|
| https://wordpress.org/plugins/wpdiscuz/ | Product |
| https://wordpress.org/plugins/wpdiscuz/#developers | Product Release Notes |
| https://www.vulncheck.com/advisories/wpdiscuz-before-no-rate-limiting-on-subscription-endpoints-with-like-wildcard-bypass | Third Party Advisory |