Live › vulnerability › CVE-2026-97031
Go to dashboardGo's crypto/tls package accepted malformed ECH (Encrypted Client Hello) outer extension references, so a client could send a crafted handshake that exhausts memory in the server process. The fix makes the TLS stack reject multiple outer extension references as malformed.
Summary written from the sources below. Check the originals before acting.
First seen by InfraStack 2026-10-23 19:13 UTC, 0h before NVD. All times on this page are UTC.
| Product | Ecosystem | Affected | Fixed in |
|---|---|---|---|
| stdlib | go | >= 1.27.0-0, < 1.27.2 | 1.26.9, 1.27.2 |
Run go version on build and deploy hosts and check whether the Go stdlib is >= 1.27.0-0 and < 1.27.2, or 1.26.x before 1.26.9.
Check whether the server uses crypto/tls with Encrypted Client Hello enabled (ECH is set via the server's tls.Config); the sources do not give a config flag.
Upgrade the Go toolchain to 1.26.9 or 1.27.2 and rebuild binaries that use crypto/tls.
Each row is the first time that source carried this signal. The analyst’s rows are its own findings.
Multiple ECH outer extension references are not permitted under RFC 9849; previously, a client could send a well-crafted packet that could trigger memory exhaustion in the server process by specifying multiple references.
We now reject these as malformed and curb the memory amplification vector as a result.
This page as .md · .json · in your agent: get_signal("CVE-2026-97031")
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