๐Ÿ” CVE Alert

CVE-2026-82854

CRITICAL 9.8

Nodemailer before 8.0.3 SMTP Command Injection via envelope.size

CVSS Score
9.8
EPSS Score
0.0%
EPSS Percentile
0th

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.

CWE CWE-93
Vendor nodemailer
Product nodemailer
Published Aug 31, 2026
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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

Affected Versions

nodemailer / nodemailer
0 < 8.0.3

References

NVD โ†— CVE.org โ†— EPSS Data โ†—
github.com: https://github.com/nodemailer/nodemailer/security/advisories/GHSA-c7w3-x93f-qmm8 vulncheck.com: https://www.vulncheck.com/advisories/nodemailer-before-8.0.3-smtp-command-injection-via-envelope-size

Credits

๐Ÿ” esquilichi