Vulnerability · Published Sep 16, 2026 · Assigned by VulnCheck
CVE-2026-92595Nodemailer before 9.1.1 Security Sandbox Bypass via resolveContent
Medium 5.9
In plain English
A medium-severity security flaw in nodemailer from nodemailer. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 22% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
Nodemailer (npm package `nodemailer`) versions 9.1.0 and earlier do not honor the `disableFileAccess` and `disableUrlAccess` sandbox options when message content is resolved through the public plugin API `MailMessage.resolveContent()` using the documented legacy three-argument signature `resolveContent(data, key, callback)`. Because `shared.resolveContent()` normalizes the missing `options` argument to an empty object, the message-level flags copied into `mail.data` by the MailMessage constructor are discarded, and `resolveContentValue()` skips both access-control checks, reaching `nmfetch(url)` or `fs.createReadStream(path)`. As a result, plugin or application code that resolves untrusted message content (html, text, attachment `path` or `href`) via this API can be induced to read arbitrary local files or issue outbound HTTP(S) requests (server-side request forgery), bypassing the sandbox the application enabled. The internal paths used by `transporter.sendMail()` (`resolveAll()`, `_convertDataImages()`, and the MIME streaming path) are not affected. Fixed in version 9.1.1.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | node-nodemailer | no fix listed | DEBIAN-CVE-2026-92595 |
| Debian:13 | node-nodemailer | no fix listed | DEBIAN-CVE-2026-92595 |
| Debian:14 | node-nodemailer | 10.0.0+~8.0.1-1 | DEBIAN-CVE-2026-92595 |
| Ubuntu:22.04:LTS | node-nodemailer | no fix listed | UBUNTU-CVE-2026-92595 |
| Ubuntu:24.04:LTS | node-nodemailer | no fix listed | UBUNTU-CVE-2026-92595 |
| Ubuntu:26.04:LTS | node-nodemailer | no fix listed | UBUNTU-CVE-2026-92595 |
| Ubuntu:26.10 | node-nodemailer | no fix listed | UBUNTU-CVE-2026-92595 |
| npm | nodemailer | 9.1.1 | GHSA-8m3c-c648-2xjj |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| nodemailer | nodemailer | 0 – before 9.1.1 |
Weakness: CWE-73 · Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:L/A:N
References
- GitHub Security Advisory (GHSA-8m3c-c648-2xjj) vendor-advisory
- VulnCheck Advisory: Nodemailer before 9.1.1 Security Sandbox Bypass via resolveContent third-party-advisory