CVE-2026-103999 json
Ultra Addons for Contact Form 7 <= 3.5.54 - Unauthenticated Stored Cross-Site Scripting via File Upload
published 24d ago modified 24d ago also EUVD-2026-102660
- cvss
- 7.2
- 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 17%
- public exploits
- 0
- none known
Summary
The Ultra Addons for Contact Form 7 plugin for WordPress is vulnerable to Stored Cross-Site Scripting via File Upload in all versions up to, and including, 3.5.54 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The extension blocklist gatekeeper is bypassed by uploading text-type files (.txt, .csv, .vtt, .srt, .asc) whose contents begin with an HTML payload such as '<BODY onload=…>', as the check classifies these files as text/plain without inspecting their byte content.
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 24d ago
Exploit prediction
0.26% chance of exploitation in the next 30 days, higher than 17% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.2 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N |
Affected products
- themefic Ultra Addons for Contact Form 7
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
- Technology feeds
References
- wordfence.com /threat-intel/vulnerabilities/id/29b9d978-f8b0-48f9-a10e-7e61a4f4a828?source=cve
- plugins.trac.wordpress.org /browser/ultimate-addons-for-contact-form-7/tags/3.5.52/addons/database/database.php#L901
- plugins.trac.wordpress.org /browser/ultimate-addons-for-contact-form-7/tags/3.5.52/addons/database/database.php#L895
- plugins.trac.wordpress.org /browser/ultimate-addons-for-contact-form-7/tags/3.5.52/addons/database/database.php#L869
- plugins.trac.wordpress.org /browser/ultimate-addons-for-contact-form-7/tags/3.5.52/inc/functions.php#L1703
- downloads.wordpress.org /plugin/ultimate-addons-for-contact-form-7.zip
- plugins.trac.wordpress.org /changeset/3738548/ultimate-addons-for-contact-form-7/trunk/addons/database/database.php
Sources
- CVE List CVE-2026-103999
- NVD CVE-2026-103999
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.