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Fencer Vulns
critical 9.1

CVE-2026-39830 json

Invoking client can cause server deadlock on unexpected responses in golang.org/x/crypto/ssh

published 2026-05-22 5 mo ago modified 2026-09-23 47 d ago also EUVD-2026-31397 , GHSA-vgwf-h737-ff37 , GO-2026-5017

cvss
9.1
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.7%
EPSS 0.7% chance of exploitation in 30 days, percentile 52%
public exploits
0
none known

Summary

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.

Patch / fix

  • go golang.org/x/crypto 0.52.0
  • golang.org/x/crypto golang.org/x/crypto/ssh 0.52.0
  • Red Hat Cryostat 4 on RHEL 9 4.2.0-19
  • Red Hat Red Hat Enterprise Linux 10 2:1.43.1-3.el10_2, 7:5.8.2-4.el10_2
  • Red Hat Red Hat Enterprise Linux 8 8100020260701102925.afee755d
  • Red Hat Red Hat Enterprise Linux 8.8 Telecommunications Update Service 8080020260721142025.63b34585
  • Red Hat Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions 8080020260721142025.63b34585
  • Red Hat Red Hat Enterprise Linux 9 2:1.43.1-2.el9_8
  • Red Hat Red Hat Enterprise Linux 9.6 Extended Update Support 5:5.4.0-22.el9_6.5
  • Red Hat RHEM 1.0 for RHEL 9 0:1.0.3-1.el9em
  • Red Hat RHEM 1.1 for RHEL 10 0:1.1.3-1.el10em
  • Red Hat RHEM 1.1 for RHEL 9 0:1.1.3-1.el9em
  • Red Hat Cert Manager support for Red Hat OpenShift release 1.19 1786613805
  • Red Hat Cluster Observability Operator 1.5.0 1787593637
  • Red Hat DevWorkspace Operator 0.42 1782400868, 1782401674
  • Red Hat Logging Subsystem for Red Hat OpenShift 6.6 1788439505
  • Red Hat multicluster engine for Kubernetes 2.1 1784564438
  • Red Hat multicluster engine for Kubernetes 2.11 1786912006
  • Red Hat multicluster engine for Kubernetes 2.8 1784738758
  • Red Hat OpenShift API for Data Protection 1.3 1785177359, 1785177438, 1785180878
  • Red Hat OpenShift API for Data Protection 1.4 1786944540, 1786946190, 1786946294
  • Red Hat OpenShift API for Data Protection 1.5 1788859896, 1788860461
  • Red Hat OpenShift API for Data Protection 1.6 1784058822
  • Red Hat Red Hat Advanced Cluster Management for Kubernetes 2.16 1786456658
  • Red Hat Red Hat Advanced Cluster Security 4.9 1782891812
  • Red Hat Red Hat Advanced Cluster Security for Kubernetes 4.10 1782891789
  • Red Hat Red Hat Advanced Cluster Security for Kubernetes 4.11 1783352589
  • Red Hat Red Hat Edge Manager 1.0 1783502022, 1783502023, 1783502025, 1783502029, 1783502401, 1783502403, 1783502445, 1783502465, 1783502494
  • Red Hat Red Hat Edge Manager 1.1 1784126762, 1784126774, 1784126780, 1784126832, 1784127762, 1784127787, 1784127791, 1784128388, 1784128860, 1784194144, 1784194188, 1784194309, 1784194347, 1784194353, 1784194638, 1784194653, 1784194971, 1784194980, 1784195620, 1784196588
  • Red Hat Red Hat OpenShift AI 3.3 1782471656
  • golang-go.crypto Debian 14 1:0.52.0-1

debian advisories DEBIAN-CVE-2026-39830

  • google-guest-agent Ubuntu 22.04 LTS 20250116.00-0ubuntu1~22.04.3
  • google-guest-agent Ubuntu 24.04 LTS 20250116.00-0ubuntu1~24.04.4
  • google-guest-agent Ubuntu 25.10 20250506.01-0ubuntu1.2
  • google-guest-agent Ubuntu 26.04 LTS 20250506.01-0ubuntu2.1
  • lxd Ubuntu Pro 16.04 LTS 2.0.11-0ubuntu1~16.04.4+esm3
  • lxd Ubuntu Pro 18.04 LTS 3.0.3-0ubuntu1~18.04.2+esm3
  • golang-go.crypto Ubuntu Pro 16.04 LTS 1:0.0~git20151201.0.7b85b09-2ubuntu0.1~esm2
  • golang-go.crypto Ubuntu Pro 18.04 LTS 1:0.0~git20170629.0.5ef0053-2ubuntu0.1~esm2

ubuntu advisories UBUNTU-CVE-2026-39830

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • podman RHEL 9 6:5.8.2-7.el9_8
  • podman-tests RHEL 9 6:5.8.2-7.el9_8
  • podman-docker RHEL 9 6:5.8.2-7.el9_8
  • podman-remote RHEL 9 6:5.8.2-7.el9_8
  • podman-plugins RHEL 9 6:5.8.2-7.el9_8
  • flightctl edge manager 1.1 1.1.3-1.el10em
  • flightctl edge manager 1.1 1.1.3-1.el9em
  • flightctl-cli edge manager 1.1 1.1.3-1.el10em

red hat advisories RHSA-2026:69961RHSA-2026:67450RHSA-2026:49944RHSA-2026:41019RHSA-2026:37072RHSA-2026:36796

  • podman Linux Micro 6.1 5.4.2-slfo.1.1_6.1
  • distribution SLES for SAP 15 SP6, SLES for SAP 15 SP5, SLES for SAP 15 SP4 +8 more 3.1.1-150400.9.41.1
  • containerized-data-importer SLE Module for Containers 15 SP7 1.64.0-150700.9.14.1
  • kubevirt SLE Module for Containers 15 SP7 1.7.4-150700.3.30.1
  • terraform-provider-aws SLE Module for Public Cloud 15 SP5, SLE Module for Public Cloud 15 SP4 3.11.0-150200.6.18.1
  • terraform-provider-tls SLE Module for Public Cloud 15 SP5, SLE Module for Public Cloud 15 SP4 3.0.0-150200.5.15.1
  • terraform-provider-helm SLE Module for Public Cloud 15 SP5, SLE Module for Public Cloud 15 SP4 2.9.0-150200.6.23.1
  • terraform-provider-null SLE Module for Public Cloud 15 SP5, SLE Module for Public Cloud 15 SP4 3.0.0-150200.6.18.1

suse advisories SUSE-SU-2026:24378-1SUSE-SU-2026:4212-1SUSE-SU-2026:4209-1SUSE-SU-2026:3203-1SUSE-SU-2026:3056-1SUSE-SU-2026:22613-1

  • cloudflared openSUSE Leap 16.0 2026.9.1-bp160.1.1
  • containerized-data-importer1.65 openSUSE Leap 16.0 1.65.0-160000.3.1
  • glab openSUSE Leap 16.0 1.114.0-bp160.1.1
  • kubevirt1.8 openSUSE Leap 16.0 1.8.4-160000.1.1
  • govulncheck-vulndb openSUSE Leap 16.0 0.0.20260723T184607-160000.1.1
  • rclone openSUSE Leap 16.0 1.74.4-bp160.1.1
  • cosign openSUSE Leap 16.0 3.1.1-160000.1.1
  • alloy openSUSE Leap 16.0 1.17.0-160000.1.1

opensuse advisories openSUSE-SU-2026:21924-1openSUSE-SU-2026:21824-1openSUSE-SU-2026:21662-1openSUSE-SU-2026:21590-1openSUSE-SU-2026:21483-1openSUSE-SU-2026:21436-1

  • podman AlmaLinux 9 6:5.8.2-7.el9_8
  • podman-tests AlmaLinux 9 6:5.8.2-7.el9_8
  • podman-docker AlmaLinux 9 6:5.8.2-7.el9_8
  • podman-remote AlmaLinux 9 6:5.8.2-7.el9_8
  • podman-plugins AlmaLinux 9 6:5.8.2-7.el9_8
  • buildah AlmaLinux 10 2:1.43.1-3.el10_2
  • buildah-tests AlmaLinux 10 2:1.43.1-3.el10_2
  • crit AlmaLinux 8 3.18-5.module_el8.10.0+4047+545787c4

almalinux advisories ALSA-2026:69961ALSA-2026:36199ALSA-2026:35833ALSA-2026:29455

  • podman Rocky Linux 9 6:5.8.2-7.el9_8
  • podman Rocky Linux 10 7:5.8.2-4.el10_2
  • buildah Rocky Linux 10 2:1.43.1-3.el10_2
  • criu Rocky Linux 8 3.18-5.module+el8.10.0+1874+ce489889
  • criu Rocky Linux 8 3.18-5.module+el8.10.0+40047+0c0a73f4
  • criu Rocky Linux 8 3.18-5.module+el8.10.0+40133+32c21f88
  • criu Rocky Linux 8 3.18-5.module+el8.10.0+1843+6892ab28
  • criu Rocky Linux 8 3.18-5.module+el8.10.0+1948+4b5cd4a9

rocky linux advisories RLSA-2026:69961RLSA-2026:37072RLSA-2026:36199RLSA-2026:35833RLSA-2026:29455

  • cert-manager Azure Linux 3.0 1.12.15-9
  • cf-cli Azure Linux 3.0 8.7.11-6
  • docker-buildx Azure Linux 3.0 0.14.0-13
  • docker-compose Azure Linux 3.0 2.27.0-11
  • gh Azure Linux 3.0 2.62.0-16
  • kubernetes Azure Linux 3.0 1.30.10-25
  • kubevirt Azure Linux 3.0 1.7.1-7
  • moby-engine Azure Linux 3.0 25.0.3-18

azure linux advisories AZL-87399AZL-87453AZL-87633AZL-87711AZL-87771AZL-87897

Azure Linux vulnerability data, Copyright (c) Microsoft Corporation, from https://github.com/microsoft/AzureLinuxVulnerabilityData via OSV, under the MIT licence; changed: normalised to fixed package versions per release. MIT

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-39830 updated cvss 7.5

golang.org/x/crypto/ssh: golang.org/x/crypto/ssh: Denial of Service via resource leak from unsolicited SSH responses

  • Red Hat Assisted Installer for Red Hat OpenShift Container Platform 2 assisted/agent-preinstall-image-builder-rhel9
    affected: workaround, no fix available
  • Red Hat Confidential Compute Attestation openshift-sandboxed-containers/osc-rhel9-operator, openshift-sandboxed-containers/osc-podvm-payload-rhel9, openshift-sandboxed-containers/osc-cloud-api-adaptor-rhel9 Red Hat External Secrets Operator for Red Hat OpenShift external-secrets-operator/external-secrets-rhel9
    affected: workaround, no fix planned “Will not fix”
  • Red Hat Multicluster Engine for Kubernetes multicluster-engine/assisted-service-8-rhel8, multicluster-engine/assisted-service-9-rhel9, multicluster-engine/azure-service-operator-rhel9, multicluster-engine/cluster-api-provider-azure-rhel9, multicluster-engine/cluster-image-set-controller-rhel9 Red Hat OpenShift Pipelines openshift-pipelines-client, openshift-pipelines/pipelines-results-api-rhel9, openshift-pipelines/pipelines-results-watcher-rhel9, openshift-pipelines/pipelines-chains-controller-rhel9, openshift-pipelines/pipelines-pipelines-as-code-watcher-rhel9, openshift-pipelines/pipelines-pipelines-as-code-controller-rhel9 Red Hat OpenShift Serverless openshift-serverless-clients, openshift-serverless-1/kn-plugin-func-func-util-rhel9 Red Hat Advanced Cluster Management for Kubernetes 2 rhacm2/multicluster-operators-subscription-rhel9 Red Hat Advanced Cluster Security 4 advanced-cluster-security/rhacs-main-rhel8, advanced-cluster-security/rhacs-roxctl-rhel8, advanced-cluster-security/rhacs-rhel8-operator, advanced-cluster-security/rhacs-scanner-v4-rhel8
    affected: workaround, no fix available
  • Red Hat Ceph Storage 8 rhceph/grafana-rhel9 Red Hat Ceph Storage 9 rhceph-ci/alloy, rhceph/alloy-rhel10
    affected: workaround, no fix available “Fix deferred”
  • Red Hat Enterprise Linux 9 gvisor-tap-vsock, gvisor-tap-vsock-gvforwarder Red Hat Enterprise Linux 10 gvisor-tap-vsock
    affected: workaround, no fix available
  • Red Hat OpenShift AI (RHOAI) rhoai/odh-model-registry-rhel8, rhoai/odh-ogx-module-operator-rhel9 Red Hat OpenShift Container Platform 4 podman, microshift, podman-tests, podman-docker, podman-remote, microshift-olm, +45 more
    affected: workaround, no fix available, no fix planned “Will not fix”
  • Red Hat OpenShift Container Platform 5 openshift5/ose-installer-rhel9, openshift5/ose-hypershift-rhel9, openshift5/ose-csi-driver-nfs-rhel9, ose-azure-acr-image-credential-provider, openshift5/ose-baremetal-installer-rhel9, openshift5/ose-machine-config-rhel9-operator Red Hat OpenShift Dev Spaces devspaces/traefik-rhel9 Red Hat OpenShift for Windows Containers openshift4-wincw/windows-machine-config-rhel9-operator, openshift4-wincw/windows-machine-config-operator-bundle Red Hat OpenShift on AWS rosa Red Hat OpenShift Virtualization 4 kubevirt Red Hat Quay 3 quay/quay-builder-rhel8, quay/quay-builder-rhel9
    +1 more products
    Red Hat Trusted Artifact Signer rhtas/ec-rhel9, rhtas/rhtas-console-rhel9, rhtas/policy-controller-rhel9, rhtas/model-validation-agent-rhel9
    affected: workaround, no fix available
  • Red Hat Zero Trust Workload Identity Manager zero-trust-workload-identity-manager/spiffe-spire-agent-rhel9, zero-trust-workload-identity-manager/spiffe-spire-server-rhel9, zero-trust-workload-identity-manager/spiffe-spire-oidc-discovery-provider-rhel9 Red Hat Zero Trust Workload Identity Manager - Tech Preview zero-trust-workload-identity-manager/spiffe-spire-agent-rhel9, zero-trust-workload-identity-manager/spiffe-spire-server-rhel9, zero-trust-workload-identity-manager/spiffe-spire-oidc-discovery-provider-rhel9
    affected: workaround, no fix planned “Will not fix”
show 17 more
  • Red Hat Cert Manager support for Red Hat OpenShift release 1.17 cert-manager/cert-manager-operator-rhel9 1791788287, cert-manager/jetstack-cert-manager-rhel9 1791371069, cert-manager/jetstack-cert-manager-acmesolver-rhel9 1791371080
    fixed: vendor fix RHSA-2026:82322
  • Red Hat Cert Manager support for Red Hat OpenShift release 1.19 cert-manager/jetstack-cert-manager-rhel9 1786613805, cert-manager/jetstack-cert-manager-acmesolver-rhel9 1786613805
    fixed: vendor fix RHSA-2026:54531
  • Red Hat Cluster Observability Operator 1.5 cluster-observability-operator/cluster-observability-rhel9-operator 1787593637
    fixed: vendor fix RHSA-2026:61314
  • Red Hat Cryostat 4 on RHEL 9 cryostat/cryostat-storage-rhel9 4.2.0-19
    fixed: vendor fix RHSA-2026:48151
  • Red Hat DevWorkspace Operator 0.42 devworkspace/devworkspace-rhel9-operator 1782401674, devworkspace/devworkspace-project-clone-rhel9 1782400868
    fixed: vendor fix RHSA-2026:36808
  • Red Hat Logging Subsystem for Red Hat OpenShift 6.5 openshift-logging/cluster-logging-rhel9-operator 1789659166
    fixed: vendor fix RHSA-2026:70870
  • Red Hat Logging Subsystem for Red Hat OpenShift 6.6 openshift-logging/cluster-logging-rhel9-operator 1788439505
    fixed: vendor fix RHSA-2026:66521
  • Red Hat multicluster engine for Kubernetes 2.8 multicluster-engine/hypershift-addon-rhel9-operator 1784738758
    fixed: vendor fix RHSA-2026:47735
  • Red Hat multicluster engine for Kubernetes 2.10 multicluster-engine/hypershift-addon-rhel9-operator 1784564438
    fixed: vendor fix RHSA-2026:46885
  • Red Hat multicluster engine for Kubernetes 2.11 multicluster-engine/hypershift-addon-rhel9-operator 1786912006, multicluster-engine/cluster-api-provider-kubevirt-rhel9 1790143694
    fixed: vendor fix RHSA-2026:72848
  • Red Hat OpenShift API for Data Protection 1.3 oadp/oadp-velero-rhel9 1785180878, oadp/oadp-mustgather-rhel9 1785177359, oadp/oadp-velero-restic-restore-helper-rhel9 1785177438
    fixed: vendor fix RHSA-2026:51033
  • Red Hat OpenShift API for Data Protection 1.4 oadp/oadp-velero-rhel9 1786944540, oadp/oadp-mustgather-rhel9 1786946294, oadp/oadp-velero-restic-restore-helper-rhel9 1786946190
    fixed: vendor fix RHSA-2026:59467
  • Red Hat OpenShift API for Data Protection 1.5 oadp/oadp-velero-rhel9 1788860461, oadp/oadp-mustgather-rhel9 1788859896
    fixed: vendor fix RHSA-2026:66022
  • Red Hat OpenShift API for Data Protection 1.6 oadp/oadp-velero-rhel9 1784058822
    fixed: vendor fix RHSA-2026:43692
  • Red Hat OpenShift Security Profiles Operator 1 compliance/openshift-security-profiles-rhel8-operator 1790623030, compliance/openshift-security-profiles-operator-bundle 1790626888
    fixed: vendor fix RHSA-2026:76752
  • Red Hat Advanced Cluster Management for Kubernetes 2.16 rhacm2/volsync-rhel9 1786456658
    fixed: vendor fix RHSA-2026:54400
  • Red Hat Advanced Cluster Security 4.9 advanced-cluster-security/rhacs-scanner-rhel8 1782891812, advanced-cluster-security/rhacs-scanner-slim-rhel8 1782891812
    fixed: vendor fix RHSA-2026:36319

41 more fixed, 60 more not affected in the full advisory

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
partial
Assessed
5 mo ago

Exploit prediction

0.68% chance of exploitation in the next 30 days, higher than 52% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CISA ADP 3.1 9.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
CISA ADP 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
GitHub 3.1 9.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
CNA 3.1 9.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
CNA 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected packages

ecosystem package affected fixed in
go golang.org/x/crypto
<0.52.0
0.52.0

Affected products

  • golang.org/x/crypto golang.org/x/crypto/ssh
  • Red Hat Cryostat 4 on RHEL 9
  • Red Hat Red Hat Enterprise Linux 10
  • Red Hat Red Hat Enterprise Linux 8
  • Red Hat Red Hat Enterprise Linux 8.8 Telecommunications Update Service
  • Red Hat Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions
  • Red Hat Red Hat Enterprise Linux 9
  • Red Hat Red Hat Enterprise Linux 9.6 Extended Update Support
  • Red Hat RHEM 1.0 for RHEL 9
  • Red Hat RHEM 1.1 for RHEL 10
  • Red Hat RHEM 1.1 for RHEL 9
  • Red Hat Cert Manager support for Red Hat OpenShift release 1.19
  • Red Hat Cluster Observability Operator 1.5.0
  • Red Hat DevWorkspace Operator 0.42
  • Red Hat Logging Subsystem for Red Hat OpenShift 6.6
  • Red Hat multicluster engine for Kubernetes 2.1
  • Red Hat multicluster engine for Kubernetes 2.11
  • Red Hat multicluster engine for Kubernetes 2.8
  • Red Hat OpenShift API for Data Protection 1.3
  • Red Hat OpenShift API for Data Protection 1.4
  • Red Hat OpenShift API for Data Protection 1.5
  • Red Hat OpenShift API for Data Protection 1.6
  • Red Hat Red Hat Advanced Cluster Management for Kubernetes 2.16
  • Red Hat Red Hat Advanced Cluster Security 4.9
  • Red Hat Red Hat Advanced Cluster Security for Kubernetes 4.10
  • Red Hat Red Hat Advanced Cluster Security for Kubernetes 4.11
  • Red Hat Red Hat Edge Manager 1.0
  • Red Hat Red Hat Edge Manager 1.1
  • Red Hat Red Hat OpenShift AI 3.3
  • Red Hat Red Hat OpenShift AI 3.4
  • Red Hat Red Hat OpenShift Builds 1.7.3
  • Red Hat Red Hat OpenShift Builds 1.8.1
  • Red Hat Red Hat OpenShift Container Platform 4.21
  • Red Hat Red Hat Openshift Data Foundation 4.22
  • Red Hat Red Hat OpenShift GitOps 1.19
  • Red Hat Red Hat OpenShift GitOps 1.20
  • Red Hat Red Hat OpenStack Platform 16.2
  • Red Hat Red Hat Quay 3.10
  • Red Hat Red Hat Quay 3.12
  • Red Hat Red Hat Quay 3.15
  • Red Hat Red Hat Quay 3.16
  • Red Hat Red Hat Quay 3.9
  • Red Hat Red Hat Trusted Artifact Signer 1.3
  • Red Hat Red Hat Trusted Artifact Signer 1.4
  • Red Hat Assisted Installer for Red Hat OpenShift Container Platform 2
  • Red Hat Confidential Compute Attestation
  • Red Hat ExternalDNS Operator
  • Red Hat External Secrets Operator for Red Hat OpenShift
  • Red Hat Multicluster Engine for Kubernetes
  • Red Hat OpenShift API for Data Protection

Classification

Weakness
  • CWE-772 Missing Release of Resource after Effective Lifetime
  • CWE-119 Improper Restriction of Operations within the Bounds of a Memory Buffer

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.