Invoking memory leak when rejecting channels can lead to DoS in golang.org/x/crypto/ssh
Priority LOW 29CWE-924Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Partial Red Hat: 5 fixed, 39 without a fix
Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA, GitHub and Red Hat.
Summary
An authenticated SSH client that repeatedly opened channels which were rejected by the server caused unbounded memory growth, eventually crashing the server process and affecting all connected users. Rejected channels are now properly removed from the connection's internal state and released for garbage collection.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00279 20th percentileScored 2026-11-07
Fix Partial golang.org/x/crypto/ssh (golang.org/x/crypto): 0.52.0golang.org/x/crypto (Go): 0.52.0Red Hat: 7 advisoriesRed Hat: 5 fixed, 39 without a fix
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Go standard library | golang.org/x/crypto/ssh | before 0.52.0 | 0.52.0 | Patch available | CNA |
| — | golang.org/x/crypto (Go) | before 0.52.0 | 0.52.0 | Patch available | GHSA-qpw4-5x99-6vjp |
- golang.org/x/crypto/ssh VendorGo standard library Affected before 0.52.0 Fixed in 0.52.0 Patch available CNA
- golang.org/x/crypto (Go) Vendor— Affected before 0.52.0 Fixed in 0.52.0 Patch available GHSA-qpw4-5x99-6vjp
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:golang:crypto:*:*:*:*:*:go:*:* | before 0.52.0 | Vulnerable | Go standard library |
- cpe:2.3:a:golang:crypto:*:*:*:*:*:go:*:* Versions before 0.52.0 Vulnerable ·Go standard library
Remediation
- Fix · CNA golang.org/x/crypto/ssh (golang.org/x/crypto) Fixed in 0.52.0
- Fix · GHSA-qpw4-5x99-6vjp golang.org/x/crypto (Go) Fixed in 0.52.0 Advisory →
Red Hat 7 advisories
- RHSA-2026:82322 Released 2026-10-13 · Red Hat rating Importantcert-manager Operator for Red Hat OpenShift 1.17.2
- Cert Manager support for Red Hat OpenShift release 1.17 registry.redhat.io/cert-manager/cert-manager-operator-rhel9
- RHSA-2026:82304 Released 2026-10-13 · Red Hat rating Importantcert-manager Operator for Red Hat OpenShift 1.17.2
- Cert Manager support for Red Hat OpenShift release 1.17 registry.redhat.io/cert-manager/jetstack-cert-manager-acmesolver-rhel9, registry.redhat.io/cert-manager/jetstack-cert-manager-rhel9
- RHSA-2026:66561 Released 2026-09-11 · Red Hat rating ImportantRed Hat Hardened Images RPMs bug fix and enhancement update
- Red Hat Hardened Images golang1.27-1.27.1-0.1.hum1@aarch64, golang1.27-1.27.1-0.1.hum1@src, golang1.27-1.27.1-0.1.hum1@x86_64 +10
Show 4 more Red Hat advisories
- RHSA-2026:62391 Released 2026-09-02 · Red Hat rating ImportantRed Hat Hardened Images RPMs bug fix and enhancement update
- Red Hat Hardened Images golang1.26-1.26.8-0.1.hum1@aarch64, golang1.26-1.26.8-0.1.hum1@src, golang1.26-1.26.8-0.1.hum1@x86_64 +10
- RHSA-2026:57194 Released 2026-08-19 · Red Hat rating Importantmulticluster engine for Kubernetes v2.11.5 security update
- multicluster engine for Kubernetes 2.11 registry.redhat.io/multicluster-engine/addon-manager-rhel9, registry.redhat.io/multicluster-engine/backplane-rhel9-operator, registry.redhat.io/multicluster-engine/cluster-api-provider-kubevirt-rhel9 +11
- RHSA-2026:43692 Released 2026-07-22 · Red Hat rating ImportantRed Hat OpenShift API for Data Protection
- OpenShift API for Data Protection 1.6 registry.redhat.io/oadp/oadp-velero-rhel9
- RHSA-2026:37387 Released 2026-07-09 · Red Hat rating ImportantRed Hat OpenShift Data Foundation 4.22.0 security, enhancement & bug fix update
- Red Hat Openshift Data Foundation 4.22 registry.redhat.io/odf4/cephcsi-rhel9, registry.redhat.io/odf4/cephcsi-rhel9-operator, registry.redhat.io/odf4/devicefinder-rhel9 +24
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Release ·
golang.org/x/crypto/ssh 0.52.0
9 records Highest priority Priority MEDIUM 4 MEDIUM, 5 LOW
Other records, highest priority first
- TI-2026-34255 Invoking VerifiedPublicKeyCallback permissions skip enforcement in golang.org/x/crypto/sshPriority MEDIUM 50
- TI-2026-28713 Invoking bypass of FIDO/U2F security keys physical interaction in golang.org/x/crypto/sshPriority MEDIUM 48
- TI-2026-28716 Invoking infinite loop on large channel writes in golang.org/x/crypto/sshPriority MEDIUM 46
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Assisted Installer for Red Hat OpenShift Container Platform 2 | Affected | No fix yet: Fix deferred |
| Builds for Red Hat OpenShift | Affected | No fix yet: Fix deferred |
| Confidential Compute Attestation | Affected | No fix yet: Fix deferred |
| Cryostat 4 | Affected | No fix yet: Fix deferred |
| External Secrets Operator for Red Hat OpenShift | Affected | No fix yet: Fix deferred |
| Multicluster Engine for Kubernetes | Affected | No fix yet: Fix deferred |
| Multicluster Global Hub | Affected | No fix yet: Fix deferred |
| OpenShift API for Data Protection | Affected | No fix yet: Fix deferred |
| OpenShift Pipelines | Affected | No fix yet: Fix deferred |
| OpenShift Serverless | Affected | No fix yet: Fix deferred |
| Red Hat Advanced Cluster Management for Kubernetes 2 | Affected | No fix yet: Fix deferred |
| Red Hat Advanced Cluster Security 4 | Affected | No fix yet: Fix deferred |
| Red Hat Ceph Storage 5 | Affected | No fix yet: Fix deferred |
| Red Hat Ceph Storage 6 | Affected | No fix yet: Fix deferred |
| Red Hat Ceph Storage 7 | Affected | No fix yet: Fix deferred |
| Red Hat Ceph Storage 8 | Affected | No fix yet: Fix deferred |
| Red Hat Ceph Storage 9 | Affected | No fix yet: Fix deferred |
| Red Hat Edge Manager 1 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 10 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 8 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 9 | Affected | No fix yet: Fix deferred |
| Red Hat Hardened Images | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift AI (RHOAI) | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift Container Platform 4 | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift Container Platform 5 | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift Dev Spaces | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift Dev Workspaces Operator | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift GitOps | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift Virtualization 4 | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift for Windows Containers | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift on AWS | Affected | No fix yet: Fix deferred |
| Red Hat OpenStack Platform 16.2 | Affected | No fix yet: Fix deferred |
| Red Hat OpenStack Platform 17.1 | Affected | No fix yet: Fix deferred |
| Red Hat OpenStack Platform 18.0 | Affected | No fix yet: Fix deferred |
| Red Hat Quay 3 | Affected | No fix yet: Fix deferred |
| Red Hat Trusted Artifact Signer | Affected | No fix yet: Fix deferred |
| Security Profiles Operator | Affected | No fix yet: Fix deferred |
| Zero Trust Workload Identity Manager | Affected | No fix yet: Fix deferred |
| Zero Trust Workload Identity Manager - Tech Preview | Affected | No fix yet: Fix deferred |
| Cert Manager support for Red Hat OpenShift release 1.17 | Fixed | RHSA-2026:82304, RHSA-2026:82322 |
| OpenShift API for Data Protection 1.6 | Fixed | RHSA-2026:43692 |
| Red Hat Hardened Images | Fixed | RHSA-2026:62391, RHSA-2026:66561 |
| Red Hat Openshift Data Foundation 4.22 | Fixed | RHSA-2026:37387 |
| multicluster engine for Kubernetes 2.11 | Fixed | RHSA-2026:57194 |
Not affected: 3 products
- OpenShift API for Data Protection 1.6
- Red Hat Openshift Data Foundation 4.22
- multicluster engine for Kubernetes 2.11
Timeline
- 2026-10-02 Threatist record created from CVE-2026-39827
- 2026-10-03 Alias added: GHSA-qpw4-5x99-6vjp
- 2026-10-14 Fix available: RHSA-2026:82304 · Red Hat
- 2026-10-14 Fix available: RHSA-2026:82322 · Red Hat
- 2026-10-15 Fix available: Cert Manager support for Red Hat OpenShift release 1.17 · Red Hat
- 2026-10-16 Affected versions changed · Red Hat
- 2026-10-30 Affected versions changed · Red Hat
References
More Go standard library Crypto vulnerabilities
- TI-2023-26623 The SSH transport protocol with certain OpenSSH extensions, found in OpenSSH before 9.6… CVSS 3.1MEDIUM 5.9
- TI-2026-30791 Invoking auth bypass via unenforced @revoked status in golang.org/x/crypto/ssh/knownhosts CVSS 3.1CRITICAL 9.1
- TI-2026-34255 Invoking VerifiedPublicKeyCallback permissions skip enforcement in golang.org/x/crypto/ssh CVSS 3.1CRITICAL 10.0
- TI-2026-28715 Invoking key constraints not enforced in golang.org/x/crypto/ssh/agent CVSS 3.1CRITICAL 9.1
- TI-2026-28714 Invoking agent constraints dropped when forwarding keys in golang.org/x/crypto/ssh/agent CVSS 3.1CRITICAL 9.1
- TI-2026-28713 Invoking bypass of FIDO/U2F security keys physical interaction in golang.org/x/crypto/ssh CVSS 3.1CRITICAL 9.1
Sources
- CVE-2026-39827 · CVE Program
- CVE-2026-39827 · NVD
- FIRST EPSS
- GHSA-qpw4-5x99-6vjp · GitHub Advisory Database · CC BY 4.0
- CVE-2026-39827 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences