CVE-2026-77820 json
WPComplete <= 2.9.9.0 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'empty' Shortcode Attribute
published last mo. modified last mo. also EUVD-2026-83465
- cvss
- 6.4
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 26%
- public exploits
- 0
- none known
Summary
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.
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- last mo.
Exploit prediction
0.33% chance of exploitation in the next 30 days, higher than 26% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 6.4 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N |
Affected products
- stellarwp WPComplete
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
- Technology feeds
References
- wordfence.com /threat-intel/vulnerabilities/id/5b91bb81-b5e4-4a50-833b-e2e98ccc09ff?source=cve
- plugins.trac.wordpress.org /browser/wpcomplete/tags/2.9.5.7/public/class-wpcomplete-public.php#L1859
- plugins.trac.wordpress.org /browser/wpcomplete/tags/2.9.5.7/public/class-wpcomplete-public.php#L1802
- plugins.trac.wordpress.org /browser/wpcomplete/tags/2.9.5.7/public/class-wpcomplete-public.php#L1692
- plugins.trac.wordpress.org /browser/wpcomplete/tags/2.9.5.7/includes/class-wpcomplete.php#L305
Sources
- CVE List CVE-2026-77820
- NVD CVE-2026-77820
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.