CVE-2026-3455Public exploitNetwork attack vector

Script execution via unescaped email URLs

Published Mar 3, 2026 · Updated Mar 3, 2026

Cross-site scripting in Nodemailer MailParser before 3.9.3 allows remote attackers to execute script in victim browsers via email URLs. The textToHtml() path inserts a detected URL and its link text into an HTML anchor without escaping double quotes or HTML entities, so crafted content breaks out of the href attribute. Exploitation requires a consuming application to render the generated textAsHtml output and victim interaction with the injected link, enabling script execution in that application's browser origin.

CVSS severity6.1
Medium
EPSS probability0.31%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Cross-site scripting in Nodemailer MailParser before 3.9.3 allows remote attackers to execute script in victim browsers via email URLs. The textToHtml() path inserts a detected URL and its link text into an HTML anchor without escaping double quotes or HTML entities, so crafted content breaks out of the href attribute. Exploitation requires a consuming application to render the generated textAsHtml output and victim interaction with the injected link, enabling script execution in that application's browser origin.

The record

CVE
CVE-2026-3455
Published
Mar 3, 2026
Updated
Mar 3, 2026
Vendor
Nodemailer
Product
MailParser
Classifications
CWE-79, T1204.001
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 3, 2026CVE publishedPublication date reported by the CVE source.
  2. Mar 3, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <3.9.3

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Nodemailer · MailParserversion=0 <3.9.3

Published CVSS scores

2.0SnykCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/SC:L/SI:L/SA:N/E:P
6.1SnykCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1204.001User Execution: Malicious Link

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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