A flaw in Node.js HTTP client can cause a request desynchronization for Node.js-based forwarding proxies that rebuild outbound headers…

Description

A flaw in Node.js HTTP client can cause a request desynchronization for Node.js-based forwarding proxies that rebuild outbound headers from the visible `IncomingMessage` headers while piping the original body to a reused backend connection. Node.js can omit headers beyond `maxHeadersCount` / `maxHeaderPairs` from `req.headers`, `req.rawHeaders`, and `req.headersDistinct`, while still using those omitted headers internally for HTTP message framing. In particular, `Content-Length` can be hidden from userland while the request body is still delivered. This vulnerability affects all supported release lines: **Node.js 22**, **Node.js 24**, and **Node.js 26**.

Scores

EPSS (exploitation in 30 days)

0.27% · top 81% of all CVEs (6 Nov 2026)

CISA SSVC

Exploitation: none · Automatable: no · Technical impact: partial

The list uses the assigner's score when there is one, then CISA's, then NVD's: Low 3.7.

Weakness

• CWE-444 HTTP Request Smuggling (opens in a new tab)All about CWE-444 and its CVEs

Affected products

• nodejs · node

  • affected 22.22.3 – ≤ 22.22.3
  • affected 24.16.0 – ≤ 24.16.0
  • affected 26.3.0 – ≤ 26.3.0

References (1)

• https://hackerone.com/reports/3564941 (opens in a new tab)

Sources

The same CVE in the primary databases and aggregators, to check against.

• CVE.org record (opens in a new tab)
• CVE List JSON (GitHub) (opens in a new tab)
• NVD (opens in a new tab)
• FIRST EPSS (opens in a new tab)
• OSV.dev (opens in a new tab)
• GitHub Advisories (opens in a new tab)
• CIRCL Vulnerability-Lookup (opens in a new tab)

Badge for a README or a ticket

[![CVE-2026-48932](https://trackcve.app/badge/CVE-2026-48932.svg)](https://trackcve.app/cve/CVE-2026-48932)

Record last updated 1 Sept 2026, 14:48 UTC.