CVE-2026-100700

nodemailer before 10.0.6 contains a denial of service vulnerability in the addressparser free-text fallback regex pattern that exhibits quadratic backtracking behavior. Attackers can supply crafted email header values with long whitespace-free runs to block the Node.js event loop for tens of seconds, causing service unavailability.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/nodemailer/nodemailer/security/advisories/GHSA-v53p-9fqp-m79j
https://www.vulncheck.com/advisories/nodemailer-before-10.0.6-denial-of-service-via-addressparser
https://github.com/nodemailer/nodemailer/security/advisories/GHSA-v53p-9fqp-m79j

Configurations

No configuration.

History

28 Sep 2026, 16:17

Type	Values Removed	Values Added
References	~~() https://github.com/nodemailer/nodemailer/security/advisories/GHSA-v53p-9fqp-m79j -~~	() https://github.com/nodemailer/nodemailer/security/advisories/GHSA-v53p-9fqp-m79j -

26 Sep 2026, 14:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-26 14:16

Updated : 2026-09-30 16:32

NVD link : CVE-2026-100700

Mitre link : CVE-2026-100700

CVE.ORG link : CVE-2026-100700

JSON object : View

Products Affected

No product.

CWE

CWE-407

Inefficient Algorithmic Complexity

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