CVE-2026-86813 (GCVE-0-2026-86813)
Vulnerability from cvelistv5 – Published: 2026-09-11 10:56 – Updated: 2026-09-11 12:06
VLAI
EPSS
VEX
Title
MetForm < 4.1.9 - Unauthenticated Email Header Injection via Notification Reply-To
Summary
The MetForm WordPress plugin before 4.1.9 does not properly neutralize newline characters in user-submitted values that are placed into notification email headers, allowing unauthenticated attackers to inject additional email headers, such as Bcc, into the emails the site sends when a submitted field value is configured to populate a header.
Severity
4.8 (Medium)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-11 12:05 UTC
CWE
- CWE-93 Improper Neutralization of CRLF Sequences ('CRLF Injection')
- CWE-93 - Improper Neutralization of CRLF Sequences ('CRLF Injection')
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://wpscan.com/vulnerability/afda2a26-b965-42… | exploitvdb-entrytechnical-description |
Impacted products
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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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