Inefficient Algorithmic Complexity in nodemailer - #VU153021
Published: September 30, 2026
Vulnerability identifier: #VU153021
CSH Severity: Low
CVSS v4: 7.1 [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-ID: N/A
CWE-ID: CWE-407
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to cause a denial of service.
The vulnerability exists due to inefficient algorithmic complexity in the DKIM message parser's header-unfolding loop when DKIM-signing an outbound message with a header folded into many continuation lines. A remote user can supply a large header value to cause a denial of service.
DKIM signing must be enabled.
Affected software
nodemailer
Remediation
Install security update from vendor's website.
nodemailer - update to 10.0.10