CVE-2026-92597 (GCVE-0-2026-92597)

Vulnerability from cvelistv5 – Published: 2026-09-16 21:47 – Updated: 2026-09-17 19:23
VLAI
Title
Nodemailer before 9.1.0 Email Domain Validation Bypass via RFC 5322 Comment
Summary
Nodemailer versions >= 6.9.16 and < 9.1.0 mis-parse RFC 5322 comments in email addresses: in lib/addressparser, a comment closed immediately before a non-break character causes the tokenizer to concatenate the atoms surrounding the comment instead of treating the comment as folding whitespace that terminates the domain. A recipient address such as user@good-corp.com(x)evil.com is therefore read by Nodemailer as the single domain good-corp.comevil.com (registrable domain comevil.com, which an attacker can register) and used for both the SMTP envelope (RCPT TO) and the emitted To:/From: headers, while a conformant RFC 5322 parser terminates the domain at the comment and reads good-corp.com. An application that validates the recipient domain with a strict RFC 5322 parser (without inspecting parse defects) or a naive prefix/substring allow-list and then hands the raw address to Nodemailer can be induced to deliver mail to a domain the attacker controls. Fixed in 9.1.0.
Severity
8.3 (High)
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N
6.5 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-17 19:17 UTC
CWE
  • CWE-436 - Interpretation Conflict
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 7132 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
nodemailer nodemailer Affected: 6.9.16 , < 9.1.0 (semver)
Unaffected: 9.1.0 (semver)
    cpe:2.3:a:nodemailer:nodemailer:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-09-01 00:00
Credits
e1abrador
Show details on NVD website
To clipboard 

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