Node.js HTTPS flaw leaks TLS keys and memory (CVE-2026-123864)

high severity · published 2026-11-11

An unauthenticated HTTPS client can make a Node.js server copy memory from other connections into its own response, including TLS private keys and other users' request bodies. This happens via a use-after-free and out-of-bounds heap read triggered by a zero-byte write from inside the HTTP parser.

Fixed in: 26.13.1

CVE: CVE-2026-123864

Source: NVD

Am I affected?

You are affected if the installed version is older than 26.13.1. Check the version you have and update to 26.13.1 or later. The fixed version is verified against a vendor or advisory source.

Get the fix

FixLane has a reviewed fix procedure for this incident: a read-only check first, then the fix. Ask the Telegram bot, or connect an AI agent to the FixLane MCP server and call get_fix_prompt with incident id 2541 and your operating system.