CVE-2026-110871

Nodemailer 3.0.0 before 10.0.10 Quadratic DKIM Header Unfolding Denial of Service

CVSS score

7.1

EPSS probability

%0.3

Risk score

0.0

Published

18 h ago

Overview Public Exploits (0)Newsroom Vulnerability Timeline

Patch status has not yet been verified

Resmî kaynaklarda yeterli kanıt bulunamadı. Bu sonuç “yama yok” anlamına gelmez.

Impact on My Inventory

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Vulnerability description

CVE AI research

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DayBreach AI Explanation

Verified against sources

Nodemailer Vulnerability in CVE-2026-110871

Sources read

Source agreement

Tam uyum

Evidence confidence

%55

Short explanation

Nodemailer from version 3.0.0 before 10.0.10 contains a denial of service vulnerability in MessageParser.parseHeaders that allows CPU exhaustion through quadratic header unfolding.

Why does it matter?

This vulnerability allows attackers to block the Node.js event loop and exhaust resources during DKIM signing, threatening service availability.

What should be done?

Follow vendor security advisories
Review available updates

Chain of evidence and sources2 verified claims

Nodemailer 3.0.0 ile 10.0.10 sürümleri arasında MessageParser.parseHeaders içinde kuadratik başlık açılımı kaynaklı hizmet reddi açığı bulunmaktadır.

S0 · daybreach-canonical S1 · nvd

Açıklık, DKIM imzalama sırasında Node.js olay döngüsünü bloke eden büyük alıcı listeleri veya uzun başlıklar yoluyla CPU tüketimine sebep olur.

S0 · daybreach-canonical S1 · nvd

Show the technical text from the sources

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.

CVSS 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

CWE: CWE-400

Explanation produced with the local gemini-flash-lite-latest model. Numerical metrics and the KEV, patch and exploit statuses are not determined by AI.

IMPACT: Affected Products and Software

Affected Products

The following products are affected by CVE-2026-110871 vulnerability. Where our threat engine knows the exact affected versions, they are listed below.

ID	VENDOR	PRODUCT	ACTION
1	nodemailer	nodemailer	View

Total affected vendors: 1|Products: 1

RED HAT CSAF/VEX: Product Impact Check

Red Hat has not yet published a CSAF/VEX impact record for this CVE. This does not mean “not affected”.

SCORING: CVSS from Multiple Sources

CVSS Scores

The Common Vulnerability Scoring System is a standardised framework for assessing the severity of vulnerabilities in software and systems. We collect and display CVSS scores from several sources for each CVE.

SCORE	VERSION	SEVERITY	VECTOR	SOURCE
7.1	CVSS V40	HIGH	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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X	NVD
7.1	CVSS V4_0	HIGH	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 CNA
6.5	CVSS V31	MEDIUM	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H	NVD
6.5	CVSS V3_1	MEDIUM	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H	CVE CNA

Patch and Remediation Guide

Solution & Remediation Advisory

Patch status unknown

İncelenen resmî kaynaklarda yama durumu doğrulanamadı. Bu sonuç “yama yok” anlamına gelmez.

Confirm the affected product and version against the source evidence above.

Restrict access to internet-facing services and apply network segmentation.

Until a patch is confirmed, follow the vendor advisory; do not read an unknown status as “no patch”.

Monitor server logs and network endpoints for signs of anomalous execution.

Public exploit and active exploitation status

Verified exploit intelligence

No verified public PoC, exploit repository or Metasploit module has been found for this CVE yet.

Weakness Classification and Attack Patterns (CWE & CAPEC)

CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorises the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-110871 is associated with the following CWEs:

CWE-400: Common Weakness Enumeration Entry CWE-400

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-110871 weaknesses.

CAPEC-66: SQL Injection CAPEC-126: Path Traversal CAPEC-28: OS Command Injection

Attack Vector and Accessibility

ExposureAğ üzerinden

PermissionsLow

UserGerekmiyor

Official Sources and Advisories

GitHub Security Advisory (GHSA-39m8-27wv-hr27)vendor-advisory VulnCheck Advisory: Nodemailer 3.0.0 before 10.0.10 Quadratic DKIM Header Unfolding Denial of Servicevendor-advisory

CVSS Vector Radar Chart

7.1 / 10

Vulnerability Scoring Details

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

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredLow privileges

User InteractionNone required

Confidentiality (Gizlilik)Low

Integrity (Bütünlük)None

Availability (Erişilebilirlik)High

Yama durumu bilinmiyor

İncelenen resmî kaynaklarda yama durumu doğrulanamadı. Bu sonuç “yama yok” anlamına gelmez.

Follow the vendor

nodemailer

Weakness Type (CWE & CAPEC)

CWE-400

Similar Vulnerabilities

9.3

CVE-2026-82854

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