# CVE-2026-121424: Nodemailer 3.0.0 before 10.1.4 Address Parsing Bypass via Nested Comments

Status: published. Published: 2026-11-03. Updated: 2026-11-03.

Nodemailer from 3.0.0 before 10.1.4 contains an address parsing vulnerability in addressparser that allows remote attackers to redirect recipients by ending nested RFC 5322 comments at the first closing parenthesis. Attackers can submit addresses whose nested comment hides an attacker address, bypassing conformant validators and recipient allow lists to receive mail or spoof senders in mailparser.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- nodemailer / nodemailer (nodemailer): ≥ 3.0.0; < 10.1.4 (affected, semver); 10.1.4 (unaffected, semver). Source: CNA: VulnCheck

## Severity and prioritization

- CVSS 4.0: 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; source: CNA: VulnCheck

- CVSS 3.1: 6.5 (medium); CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N; source: CNA: VulnCheck

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-20

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://github.com/nodemailer/nodemailer/security/advisories/GHSA-8c8m-p3m8-cjg8 (CNA: VulnCheck; vendor-advisory)

- https://www.vulncheck.com/advisories/nodemailer-3.0.0-before-10.1.4-address-parsing-bypass-via-nested-comments (CNA: VulnCheck; third-party-advisory)

## Provenance

- CNA: VulnCheck: https://www.cve.org/CVERecord?id=CVE-2026-121424; retrieved 2026-11-03; source updated 2026-11-03

Revision: da2a21d9b30abfbfe1965cb9c710a7b1ff22a1df19b55b8c1394574a116d72cb

Canonical: https://y2.dev/cve/CVE-2026-121424

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