CVE-2026-77820: The WPComplete plugin for WordPress is vulnerable to Stored Cross-Site Scripting via 'empty' Shortcode Attribute in all…
CVE-2026-77820 analysis covering impact, affected products, versions, remediation, and cross-checked defender guidance.
CVE-2026-77820 is a vulnerability published by NVD on 9/19/2026.
What happened
The WPComplete plugin for WordPress is vulnerable to Stored Cross-Site Scripting via 'empty' Shortcode Attribute in all versions up to, and including, 2.9.9.0 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This requires the premium version of the software in order to exploit. Please note this only affects the pro version.
Affected products and versions
- NVD has not published a normalized affected-product configuration yet.
Severity and weakness
CVSS: MEDIUM 6.4. Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N.
Weaknesses: CWE-79.
Known exploitation
No CISA KEV entry is currently attached to the NVD record.
What defenders should do
- Identify whether the affected product and version range exists in production.
- Review vendor advisories and release notes before change windows.
- Patch, upgrade, disable the vulnerable component, or apply vendor mitigations.
- Verify the running version after deployment, not only the package inventory.
Official and supporting references
- No vendor advisory tagged by NVD at draft time.