TI-2026-62454 Aliases CVE-2026-92598 GHSA-r7q5-h7cx-p54x

Nodemailer before 9.1.0 IDN/Punycode Domain Allow-list Bypass

HIGH 69CWE-436Published 2026-09-16 · Updated 2026-09-17

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 before 9.1.0 fails to apply UTS-46 normalization when encoding international domain names, causing the domain resolver to compute a different Punycode A-label than standards-compliant parsers. Attackers can craft recipient addresses with invisible characters or compatibility mappings that pass domain allow-list checks but are delivered to attacker-controlled domains via SMTP.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV

EPSS 0.00395 33rd percentileScored 2026-11-08

Fix Partial nodemailer (nodemailer): 9.1.0Red Hat: 3 without a fix

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	before 9.1.0	9.1.0	Patch available	CNA

nodemailer Vendornodemailer Affected before 9.1.0 Fixed in 9.1.0 Patch available CNA

Remediation

Fix · CNA nodemailer (nodemailer) Fixed in 9.1.0

Fixed in the same release

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

Release · 2026-09-16
nodemailer 9.1.0
3 records Highest priority Priority HIGH 2 HIGH, 1 LOW
Other records, highest priority first
- TI-2026-62452 Nodemailer before 9.1.0 Denial of Service via addressparserPriority HIGH 77
- TI-2026-62453 Nodemailer before 9.1.0 Email Domain Validation Bypass via RFC 5322 CommentPriority LOW 36
Show all 3 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

2026-10-02 Threatist record created from CVE-2026-92598
2026-10-03 Alias added: GHSA-r7q5-h7cx-p54x
2026-10-07 Affected versions changed · Red Hat
2026-10-27 Affected versions changed · Red Hat

References

Patch 2

Advisory 1

GitHub Security Advisory (GHSA-wmmp-3585-3rmp)

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

See all 27 →

Sources

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