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

• Sentry's sensitive headers are leaked when `sendDefaultPii` is set to `true` - CVE-2025-65944
• Regular Expression Denial of Service (ReDoS) in lodash (GHSA-29mw-wpgm-hmr9) - CVE-2020-28500
• Server-Side Request Forgery via /_image endpoint in Astro Cloudflare adapter - CVE-2025-58179
• CKEditor 5 cross-site scripting (XSS) vulnerability in the clipboard package - CVE-2025-58064

Tags:

npm

http-proxy-middleware