A memory leak vulnerability in the Go standard library’s SSH package (golang.org/x/crypto/ssh) can be triggered when SSH channels are rejected, potentially allowing an attacker to exhaust server memory and cause a Denial of Service. This affects any service or application built with the affected Go crypto library, including Azure-hosted workloads. Because SSH is a foundational protocol for remote access and automation, the blast radius across cloud infrastructure can be significant.

Architect’s Take: Audit your Azure workloads and internal tooling for services built with golang.org/x/crypto/ssh and prioritise patching to a fixed version of the library. Pay particular attention to any internet-facing SSH endpoints or Go-based automation pipelines, and consider rate-limiting or connection throttling as a short-term mitigation.

Original advisory: CVE-2026-39827 Invoking memory leak when rejecting channels can lead to DoS in golang.org/x/crypto/ssh