Nodemailer from 3.0.0 before 10.0.10 contains a denial of service vulnerability in MessageParser.parseHeaders that allows users to exhaust CPU through quadratic header unfolding. Attackers can supply large recipient lists or long headers that fold into tens of thousands of continuation lines, blocking the Node.js event loop during DKIM signing.
History

Tue, 20 Oct 2026 03:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Thu, 15 Oct 2026 13:30:00 +0000

Type Values Removed Values Added
Weaknesses CWE-1322
References
Metrics threat_severity

None

threat_severity

Moderate


Wed, 14 Oct 2026 23:00:00 +0000

Type Values Removed Values Added
Description Nodemailer from 3.0.0 before 10.0.10 contains a denial of service vulnerability in MessageParser.parseHeaders that allows users to exhaust CPU through quadratic header unfolding. Attackers can supply large recipient lists or long headers that fold into tens of thousands of continuation lines, blocking the Node.js event loop during DKIM signing.
Title Nodemailer 3.0.0 before 10.0.10 Quadratic DKIM Header Unfolding Denial of Service
First Time appeared Nodemailer
Nodemailer nodemailer
Weaknesses CWE-400
CPEs cpe:2.3:a:nodemailer:nodemailer:*:*:*:*:*:*:*:*
Vendors & Products Nodemailer
Nodemailer nodemailer
References
Metrics cvssV3_1

{'score': 6.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

cvssV4_0

{'score': 7.1, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published: 2026-10-14T22:52:59.681Z

Updated: 2026-10-20T02:28:10.449Z

Reserved: 2026-10-14T22:21:21.397Z

Link: CVE-2026-110871

cve-icon Vulnrichment

Updated: 2026-10-20T02:28:04.577Z

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-10-14T23:17:28.953

Modified: 2026-10-20T03:17:14.553

Link: CVE-2026-110871

cve-icon Redhat

Severity : Moderate

Publid Date: 2026-10-14T22:52:59Z

Links: CVE-2026-110871 - Bugzilla