CVE-2026-56855 — Prevent DoS on deadlocked established channel in golang.org/x/crypto/ssh
Previously, after a channel has been established, a malicious peer could send crafted messages that would deadlock the entire connection. Now, we handle all RFC 4254 channel mes…
Published: 2026-09-02 · CVSS: 7.5 · CVSS 3.1
Previously, after a channel has been established, a malicious peer could send crafted messages that would deadlock the entire connection. Now, we handle all RFC 4254 channel messages; global requests are handled explicitly. Then, treat all other messages as a protocol error and tear the connection down instead of buffering and blocking.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7