CVE-2026-56855

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://go.dev/cl/826524	Patch
https://go.dev/issue/81317	Issue Tracking Vendor Advisory
https://groups.google.com/g/golang-announce/c/1y3fb2np35U	Mailing List Vendor Advisory
https://pkg.go.dev/vuln/GO-2026-6355	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:golang:crypto:*:*:*:*:*:go:*:*

History

No history.

Information

Published : 2026-09-02 20:17

Updated : 2026-09-04 16:34

NVD link : CVE-2026-56855

Mitre link : CVE-2026-56855

CVE.ORG link : CVE-2026-56855

JSON object : View

Products Affected

golang

crypto

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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