Vulnerability Description
Nodemailer before 8.0.4 is vulnerable to SMTP command injection through the unsanitized envelope.size parameter. When an application passes a custom envelope object with a size property containing CRLF characters to sendMail(), the value is concatenated into the SMTP MAIL FROM command (as SIZE=...) without sanitization, allowing injection of arbitrary SMTP commands such as RCPT TO to silently add attacker-controlled recipients. Exploitation requires the application to expose the envelope size to attacker-controlled input, as Nodemailer does not include size in the default auto-constructed envelope.
CVSS Score
CRITICAL
Related Weaknesses (CWE)
References
- https://github.com/nodemailer/nodemailer/security/advisories/GHSA-c7w3-x93f-qmm8
- https://www.vulncheck.com/advisories/nodemailer-before-8.0.3-smtp-command-inject
FAQ
What is CVE-2026-82854?
CVE-2026-82854 is a vulnerability with a CVSS score of 9.8 (CRITICAL). Nodemailer before 8.0.4 is vulnerable to SMTP command injection through the unsanitized envelope.size parameter. When an application passes a custom envelope object with a size property containing CRL...
How severe is CVE-2026-82854?
CVE-2026-82854 has been rated CRITICAL with a CVSS base score of 9.8/10. This is considered a critical vulnerability requiring immediate attention.
Is there a patch for CVE-2026-82854?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.