Nodemailer addressparser flaw delivers mail to attacker domains
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- High
- Attack requirements
- Present
- Impact type
- —
- Confidentiality · integrity · availability
- High · Low · None
- Fix status
- Partial Red Hat: 3 without a fix
Attack profile from CVSS 4.0 · CNA. Fix status from CNA and Red Hat.
Summary
Nodemailer from 3.0.0 before 10.1.4 contains an improper input validation flaw (CWE-20) in its addressparser. The parser ends an address at a '>' inside a quoted local part, comment or domain literal. A remote, unauthenticated attacker can submit addresses that pass recipient domain checks but are delivered to an attacker-controlled domain, bypassing allow lists and disclosing message content.
Written with Claude Haiku 5.5 from the sources below · 2026-11-07
Description from the CNA
Nodemailer from 3.0.0 before 10.1.4 contains an address parsing vulnerability in addressparser that ends an angle-addr at a '>' inside a quoted local part, comment or domain literal. Attackers can submit addresses that validate as an allowed domain but are delivered to an attacker-controlled domain, bypassing recipient allow lists and disclosing message content.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| nodemailer | nodemailer | 3.0.0 to before 10.1.4 | 10.1.4 | Patch available | CNA |
- nodemailer Vendornodemailer Affected 3.0.0 to before 10.1.4 Fixed in 10.1.4 Patch available CNA
Remediation
Upgrade Nodemailer to 10.1.4. Red Hat rates this Moderate and lists Red Hat Developer Hub 1, Red Hat Enterprise Linux 10 and Self-service automation portal 2 as affected with no fix available.
Written with Claude Haiku 5.5 from the sources below · 2026-11-07
- Fix · CNA nodemailer (nodemailer) Fixed in 10.1.4
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Release ·
nodemailer 10.1.4
3 records Highest priority Priority HIGH 2 HIGH, 1 LOW
Other records, highest priority first
- TI-2026-84307 Recipient injection in Nodemailer addressparser group parsingPriority HIGH 69
- TI-2026-84306 Address parsing bypass in Nodemailer via nested commentsPriority LOW 36
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Developer Hub 1 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 10 | Affected | No fix yet: Fix deferred |
| Self-service automation portal 2 | Affected | No fix yet: Fix deferred |
Not affected: 1 product
- Red Hat Hardened Images
Timeline
- 2026-11-03 Threatist record created from CVE-2026-121426
- 2026-11-03 Alias added: GHSA-crhf-rr59-7pch
- 2026-11-03 Affected versions changed · Red Hat
- 2026-11-03 CVSS score added · Red Hat
- 2026-11-05 Priority changed: MEDIUM → LOW
- 2026-11-07 CISA SSVC decision points changed
- 2026-11-07 Priority changed: LOW → HIGH
References
More nodemailer vulnerabilities
- TI-2026-74559 ReDoS in Nodemailer SMTP AUTH mechanism detection regexes CVSS 4.0HIGH 8.7
- TI-2026-64856 nodemailer before 10.0.6 Denial of Service via addressparser CVSS 4.0HIGH 8.7
- TI-2026-62452 Nodemailer before 9.1.0 Denial of Service via addressparser CVSS 4.0HIGH 8.7
- TI-2026-61683 Nodemailer 9.1.0 through 10.0.4 Denial of Service via Quadratic Address Parsing CVSS 4.0HIGH 8.7
- TI-2025-13566 Nodemailer: nodemailer: denial of service via crafted email address header CVSS 3.1HIGH 7.5
- TI-2026-74560 Nodemailer address parser passes illegal characters to SMTP envelope CVSS 4.0MEDIUM 6.9
Sources
- CVE-2026-121426 · CVE Program
- CVE-2026-121426 · NVD
- FIRST EPSS
- GHSA-crhf-rr59-7pch · GitHub Advisory Database · CC BY 4.0
- CVE-2026-121426 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences