CVE-2026-56855

HIGH CVSS 3.1: 7.5 EPSS 0.38%
Updated Sep 04, 2026
Golang
Parameter Value
CVSS 7.5 (HIGH)
Affected Versions before 0.56.0
Fixed In 0.56.0
Type CWE-770 (Allocation Without Limits)
Vendor Golang
Public PoC No

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.

Attack Parameters

Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Privileges Required
None
No privileges needed
User Interaction
None
No user interaction needed

Impact Assessment

Confidentiality
None
No data leak
Integrity
None
No data modification
Availability
High
Complete denial of service

CVSS Vector v3.1

Vulnerable Products 1

Configuration From (including) Up to (excluding)
Golang Crypto
cpe:2.3:a:golang:crypto:*:*:*:*:*:go:*:*
0.56.0