HexBrain

Node.js · Report #3357723

Memory leak that enables remote Denial of Service against applications processing TLS client certificates

Validstatus
mediumseverity
34upvotes
12 Feb 2026disclosed

Summary

A memory leak in Node.js’s OpenSSL integration occurs when converting X.509 certificate fields to UTF-8 without freeing the allocated buffer. When applications call socket.getPeerCertificate(true), each certificate field leaks memory, allowing remote clients to trigger steady memory growth through repeated TLS connections. Over time this can lead to resource exhaustion and denial of service.

How it was found

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