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CVE-2026-110871

Status: Awaiting AnalysisHigh (7.1)—
Severity7.1High · CVSS 4.0
Exploitation probability0.25 %higher than 16% of CVEs
Active exploitationNonot in the CISA catalog
Public exploitNot knownno public code found

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

Base score
7.1
Version
4.0
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/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

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days
0.25 %
Percentile among all scored CVEs
16
Score date
10/21/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

Vector AV:N con PR:L (red con pocos privilegios) y el texto indica agotamiento de CPU por desenrollado cuadrático de cabeceras que bloquea el event loop de Node.js.

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

ATT&CK mitigations that cover these techniques

Vulnerability ScanningThreat Intelligence ProgramPrivileged Account ManagementNetwork SegmentationFilter Network TrafficDisable or Remove Feature or Program

Affected technologies (1)

⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.

Nodemailer — NodemailerAI

CWEs

References

Show 3 references

Raw JSON (NVD)

Show
{
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          "options": [
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          "version": "2.0.3",
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          "vulnIntegrityImpact": "NONE",
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          "modifiedAttackVector": "NOT_DEFINED",
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          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "vulnerabilityResponseEffort": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED"
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      "affectedData": [
        {
          "vendor": "nodemailer",
          "product": "nodemailer",
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  "published": "2026-10-14T23:17:28.953",
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    {
      "url": "https://github.com/nodemailer/nodemailer/security/advisories/GHSA-39m8-27wv-hr27",
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      "lang": "en",
      "value": "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."
    }
  ],
  "lastModified": "2026-10-20T03:17:14.553",
  "sourceIdentifier": "disclosure@vulncheck.com"
}