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.
History

Wed, 09 Sep 2026 12:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-833
References
Metrics threat_severity

None

threat_severity

Moderate


Fri, 04 Sep 2026 16:45:00 +0000

Type Values Removed Values Added
CPEs cpe:2.3:a:golang:crypto:*:*:*:*:*:go:*:*

Thu, 03 Sep 2026 18:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-667

Thu, 03 Sep 2026 16:00:00 +0000

Type Values Removed Values Added
First Time appeared Golang
Golang crypto
Vendors & Products Golang
Golang crypto

Thu, 03 Sep 2026 15:30:00 +0000

Type Values Removed Values Added
Weaknesses CWE-770
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Thu, 03 Sep 2026 10:00:00 +0000

Type Values Removed Values Added
Weaknesses CWE-667

Wed, 02 Sep 2026 19:45:00 +0000

Type Values Removed Values Added
Description 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.
Title Prevent DoS on deadlocked established channel in golang.org/x/crypto/ssh
References

cve-icon MITRE

Status: PUBLISHED

Assigner: Go

Published: 2026-09-02T19:37:05.807Z

Updated: 2026-09-03T14:14:40.169Z

Reserved: 2026-06-23T15:10:49.353Z

Link: CVE-2026-56855

cve-icon Vulnrichment

Updated: 2026-09-03T14:14:13.081Z

cve-icon NVD

Status : Analyzed

Published: 2026-09-02T20:17:36.397

Modified: 2026-09-04T16:34:56.823

Link: CVE-2026-56855

cve-icon Redhat

Severity : Moderate

Publid Date: 2026-09-02T19:37:05Z

Links: CVE-2026-56855 - Bugzilla