CVE-2026-86833 (GCVE-0-2026-86833)
Vulnerability from cvelistv5 – Published: 2026-10-07 06:47 – Updated: 2026-10-07 09:49
VLAI
EPSS
VEX
Title
MetForm < 4.3.1 - Unauthenticated HTML Injection in Notification Emails via Field Shortcodes
Summary
The MetForm WordPress plugin before 4.3.1 does not sanitize or escape submitted form-field values before inserting them into the HTML body of its email notifications, allowing unauthenticated attackers to inject arbitrary markup into the administrator and submitter notification emails the site sends.
Severity
5.4 (Medium)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-07 09:49 UTC
CWE
- CWE-74 Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')
- CWE-74 - Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://wpscan.com/vulnerability/6d6850d6-6fdf-4b… | exploitvdb-entrytechnical-description |
Impacted products
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| Author | Source | Type | Date | Other |
|---|
Nomenclature
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The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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