TI-2026-74560 Aliases CVE-2026-110870

Nodemailer address parser passes illegal characters to SMTP envelope

HIGH 70CWE-20Published 2026-10-14 · Updated 2026-10-26

Key facts

Attack vector: Network
Privileges required: None
User interaction: None
Attack complexity: Low
Attack requirements: None
Impact type: —
Confidentiality · integrity · availability: None · 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 10.0.13 has improper input validation (CWE-20) in its address parser. The parser fails to strip RFC 5322 comments inside angle-bracket addresses, so illegal characters reach envelope.to and RCPT TO. A remote attacker without privileges or user interaction can supply crafted recipients, causing rejected delivery or parser conflicts that bypass domain allow-lists.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

Description from the CNA

Nodemailer from 3.0.0 before 10.0.13 contains an improper input validation vulnerability in its address parser that fails to strip RFC 5322 comments inside angle-bracket addresses. Attackers can supply recipients like a display name with a parenthesized comment in the domain, so illegal characters reach envelope.to and RCPT TO, causing rejected delivery or parser interpretation conflicts that bypass domain allow-lists.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV

EPSS 0.00266 18th percentileScored 2026-11-07

Fix Partial nodemailer (nodemailer): 10.0.13Red Hat: 3 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: Poc
Automatable: Yes
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 10.0.13	10.0.13	Patch available	CNA

nodemailer Vendornodemailer Affected 3.0.0 to before 10.0.13 Fixed in 10.0.13 Patch available CNA

Remediation

Upgrade Nodemailer to 10.0.13. Red Hat 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 · 2026-10-28

Fix · CNA nodemailer (nodemailer) Fixed in 10.0.13

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

Release · 2026-10-14
nodemailer 10.0.13
2 records Highest priority Priority HIGH 2 HIGH
Other records, highest priority first
- TI-2026-74559 ReDoS in Nodemailer SMTP AUTH mechanism detection regexesPriority HIGH 77
Show all 2 records →

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

2026-10-15 Threatist record created from CVE-2026-110870
2026-10-16 Priority changed: MEDIUM → LOW
2026-10-16 Affected versions changed · Red Hat
2026-10-16 CVSS score added · Red Hat
2026-10-26 CISA SSVC decision points changed
2026-10-26 Priority changed: LOW → HIGH
2026-10-27 Affected versions changed · Red Hat

References

Advisory 1

GitHub Security Advisory (GHSA-g73g-hqqh-jr95)

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-2026-64855 Nodemailer before 10.0.9 Malformed Envelope Recipient via RFC 5322 Comment CVSS 4.0MEDIUM 6.9

See all 27 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences