http-proxy-middleware can call writeBody twice because "else if" is not used

Description

In http-proxy-middleware before 2.0.8 and 3.x before 3.0.4, writeBody can be called twice because “else if” is not used.

Recommendation

Update the http-proxy-middleware package to the latest compatible version. Followings are version details:

• Affected version(s): **>= 1.3.0, < 2.0.8

  >= 3.0.0, < 3.0.4**

• Patched version(s): **2.0.8

  3.0.4**

References

• GHSA-4www-5p9h-95mh
• CVE-2025-32996
• CWE-670
• CAPEC-310
• OWASP 2021-A6

Related Issues

• http-proxy-middleware allows fixRequestBody to proceed even if bodyParser has failed - CVE-2025-32997
• Denial of service in http-proxy-middleware - CVE-2024-21536
• Astro's middleware authentication checks based on url.pathname can be bypassed via url encoded values - CVE-2025-64765
• Parsed HTML anchor links in Markdown provided to parseMarkdown can result in XSS in @nuxtjs/mdc - CVE-2025-24981

Tags:

npm

http-proxy-middleware