Resource Leak in golang.org/x/crypto/ssh <0.52.0 via Global Request Buffers
CVE-2026-39830 Published on May 22, 2026

Invoking client can cause server deadlock on unexpected responses in golang.org/x/crypto/ssh
A malicious SSH peer could send unsolicited global request responses to fill an internal buffer, blocking the connection's read loop. The blocked goroutine could not be released by calling Close(), resulting in a resource leak per connection. Unsolicited global responses are now discarded.

NVD

Vulnerability Analysis

CVE-2026-39830 is exploitable with network access, and does not require authorization privileges or user interaction. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have no impact on confidentiality and integrity, and a high impact on availability.

Attack Vector:
NETWORK
Attack Complexity:
LOW
Privileges Required:
NONE
User Interaction:
NONE
Scope:
UNCHANGED
Confidentiality Impact:
NONE
Integrity Impact:
NONE
Availability Impact:
HIGH

Weakness Type

Missing Release of Resource after Effective Lifetime

The software does not release a resource after its effective lifetime has ended, i.e., after the resource is no longer needed. When a resource is not released after use, it can allow attackers to cause a denial of service by causing the allocation of resources without triggering their release. Frequently-affected resources include memory, CPU, disk space, power or battery, etc.


Products Associated with CVE-2026-39830

You can be notified by email with stack.watch whenever vulnerabilities like CVE-2026-39830 are published in these products:

Canonical Ubuntu Linux
 
Red Hat Enterprise Linux (RHEL)
 
Red Hat Assisted Installer
 
Red Hat Openshift Builds
 
Red Hat Cert Manager
 
Red Hat Confidential Compute Attestation
 
Red Hat Cryostat
 
Red Hat External Secrets Operator
 
Red Hat Multicluster Engine
 
Red Hat Openshift Api Data Protection
 
Red Hat Openshift Pipelines
 
Red Hat Serverless
 
Red Hat Acm
 
Red Hat Advanced Cluster Security
 
Red Hat Ceph Storage
 
Red Hat Edge Manager
 
Red Hat Openshift Ai
 
Red Hat Openshift
 
Red Hat Openshift Data Foundation
 
Red Hat Openshift Devspaces
 
Red Hat Devworkspace
 
Red Hat Windows Machine Config
 
Red Hat Openshift Gitops
 
Red Hat Openshift Service On Aws
 
Red Hat Container Native Virtualization
 
Red Hat Openstack
 
Red Hat Quay
 
Red Hat Trusted Artifact Signer
 
Red Hat Openshift Security Profiles Operator
 
Red Hat Zero Trust Workload Identity Manager
 

Affected Versions

golang.org/x/crypto/ssh: Red Hat RHEM 1.0 for RHEL 9: Red Hat Enterprise Linux AppStream (v. 10): Red Hat Enterprise Linux AppStream (v. 8): Red Hat Enterprise Linux AppStream (v. 9): Red Hat Enterprise Linux CodeReady Linux Builder (v. 10): Red Hat DevWorkspace Operator 0.42: Red Hat Advanced Cluster Security for Kubernetes 4.10: Red Hat Advanced Cluster Security for Kubernetes 4.11: Red Hat Advanced Cluster Security for Kubernetes 4.9: Red Hat Edge Manager 1.0: Red Hat OpenShift AI 3.3: Red Hat OpenShift Builds 1.7.4: Red Hat Openshift Data Foundation 4.22: Red Hat Trusted Artifact Signer 1.4: Assisted Installer for Red Hat OpenShift Container Platform 2: cert-manager Operator for Red Hat OpenShift: Red Hat Confidential Compute Attestation: External Secrets Operator for Red Hat OpenShift: Red Hat Multicluster Engine for Kubernetes: Red Hat OpenShift API for Data Protection: Red Hat OpenShift Pipelines: Red Hat OpenShift Serverless: Red Hat Advanced Cluster Management for Kubernetes 2: Red Hat Advanced Cluster Security 4: Red Hat Ceph Storage 9: Red Hat Edge Manager 1: Red Hat Enterprise Linux 10: Red Hat Enterprise Linux 9: Red Hat OpenShift AI (RHOAI): Red Hat OpenShift Container Platform 4: Red Hat OpenShift Dev Spaces: Red Hat OpenShift for Windows Containers: Red Hat OpenShift GitOps: Red Hat OpenShift on AWS: Red Hat OpenShift Virtualization 4: Red Hat OpenStack Platform 16.2: Red Hat OpenStack Platform 17.1: Red Hat Quay 3: Red Hat Trusted Artifact Signer: Red Hat Security Profiles Operator: Red Hat Zero Trust Workload Identity Manager: Red Hat Zero Trust Workload Identity Manager - Tech Preview: Red Hat Cryostat 4: Red Hat Openshift Data Foundation 4: Red Hat OpenStack Platform 18.0:

Exploit Probability

EPSS
0.31%
Percentile
22.88%

EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.