Resource Leak Vulnerability in SSH Connections of Go Programming Language
CVE-2026-39830

9.1CRITICAL

Key Information:

Vendor

Golang.org/x/crypto

Status
Golang.org/x/crypto/ssh
Vendor
CVE Published:
22 May 2026

What is CVE-2026-39830?

An attacker exploiting a vulnerability in the Go programming language could intentionally send unsolicited global request responses during SSH connections. This malicious action fills an internal buffer which subsequently blocks the connection's read loop, leading to a resource leak that accumulates with each connection. The warning flags raised by this vulnerability signal an urgent need for developers to ensure that unsolicited global responses are properly handled. As a resolution, adjustments have been made to discard these unsolicited global responses effectively, thereby enhancing the security posture of the affected versions.

Affected Version(s)

golang.org/x/crypto/ssh 0 < 0.52.0

References

https://go.dev/issue/79564
https://groups.google.com/g/golang-announce/c/a082jnz-LvI
https://go.dev/cl/781640

CVSS V3.1

Score:
9.1
Severity:
CRITICAL
Confidentiality:
High
Integrity:
None
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

NCC Group Cryptography Services, sponsored by Teleport
.