Denial of service in gopkg.in/yaml.v2
Priority MEDIUM 58Published · Updated
Key facts
- Attack vector
- Local
- Privileges required
- None
- User interaction
- Required
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Partial Red Hat: 3 fixed, 13 without a fix
Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA, GitHub and Red Hat.
Summary
Due to unbounded alias chasing, a maliciously crafted YAML file can cause the system to consume significant system resources. If parsing user input, this may be used as a denial of service vector.
Why it matters now
Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00427 37th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Partial gopkg.in/yaml.v2 (gopkg.in/yaml.v2): 2.2.3gopkg.in/yaml.v2 (Go): 2.2.3Red Hat: 6 advisoriesRed Hat: 3 fixed, 13 without a fix
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- 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 |
|---|---|---|---|---|---|
| gopkg.in/yaml.v2 | gopkg.in/yaml.v2 | before 2.2.3 | 2.2.3 | Patch available | CNA |
| github.com/go-yaml/yaml | github.com/go-yaml/yaml | — | — | No fix listed | CNA |
| — | gopkg.in/yaml.v2 (Go) | before 2.2.3 | 2.2.3 | Patch available | GHSA-r88r-gmrh-7j83 |
| — | github.com/go-yaml/yaml (Go) | up to 2.1.0 | — | No fix listed | GHSA-r88r-gmrh-7j83 |
- gopkg.in/yaml.v2 Vendorgopkg.in/yaml.v2 Affected before 2.2.3 Fixed in 2.2.3 Patch available CNA
- github.com/go-yaml/yaml Vendorgithub.com/go-yaml/yaml Affected — Fixed in — No fix listed CNA
- gopkg.in/yaml.v2 (Go) Vendor— Affected before 2.2.3 Fixed in 2.2.3 Patch available GHSA-r88r-gmrh-7j83
- github.com/go-yaml/yaml (Go) Vendor— Affected up to 2.1.0 Fixed in — No fix listed GHSA-r88r-gmrh-7j83
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:yaml_project:yaml:*:*:*:*:*:go:*:* | before 2.2.3 | Vulnerable | Yaml Project |
- cpe:2.3:a:yaml_project:yaml:*:*:*:*:*:go:*:* Versions before 2.2.3 Vulnerable ·Yaml Project
Remediation
- Fix · CNA gopkg.in/yaml.v2 (gopkg.in/yaml.v2) Fixed in 2.2.3
- Fix · GHSA-r88r-gmrh-7j83 gopkg.in/yaml.v2 (Go) Fixed in 2.2.3 Advisory →
Red Hat 6 advisories
- RHSA-2023:3615 Released 2023-06-24 · Red Hat rating ModerateOpenShift Container Platform 4.12.22 bug fix and security update
- Red Hat OpenShift Container Platform 4.12 openshift4/ose-openshift-controller-manager-rhel8
- RHSA-2023:3742 Released 2023-06-21 · Red Hat rating ImportantRed Hat OpenShift Data Foundation 4.13.0 security and bug fix update
- RHODF 4.13 for RHEL 9 odf4/cephcsi-rhel9, odf4/mcg-core-rhel9, odf4/mcg-rhel9-operator +7
- RHSA-2023:1326 Released 2023-05-17 · Red Hat rating ImportantOpenShift Container Platform 4.13.0 security update
- Red Hat OpenShift Container Platform 4.13 openshift4/cloud-network-config-controller-rhel8, openshift4/egress-router-cni-rhel8, openshift4/kubevirt-csi-driver-rhel8 +47
Show 3 more Red Hat advisories
- RHSA-2023:0569 Released 2023-02-07 · Red Hat rating ImportantOpenShift Container Platform 4.12.2 security update
- Red Hat OpenShift Container Platform 4.12 openshift4/ose-installer, openshift4/ose-machine-config-operator
- RHSA-2023:0570 Released 2023-02-07 · Red Hat rating ModerateOpenShift Container Platform 4.12.2 security update
- Red Hat OpenShift Container Platform 4.12 openshift4/metallb-rhel8-operator
- RHSA-2022:7398 Released 2023-01-17 · Red Hat rating ModerateOpenShift Container Platform 4.12.0 packages and security update
- Ironic content for Red Hat OpenShift Container Platform 4.12 crudini-0.9.3-4.el9, future-0.18.2-9.el9.1, openstack-ironic-1:21.0.1-0.20221114235951.fe64d5e.el9 +47
- Red Hat OpenShift Container Platform 4.12 NetworkManager-1:1.36.0-8.el8_6, NetworkManager-adsl-1:1.36.0-8.el8_6, NetworkManager-bluetooth-1:1.36.0-8.el8_6 +47
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Migration Toolkit for Containers | Affected | No fix planned: Will not fix |
| OpenShift Developer Tools and Services | Affected | No fix yet |
| OpenShift Pipelines | Affected | No fix planned: Will not fix |
| OpenShift Serverless | Affected | No fix planned: Will not fix |
| Red Hat Advanced Cluster Security 3 | Affected | No fix planned: Will not fix |
| Red Hat Ansible Automation Platform 2 | Affected | No fix yet |
| Red Hat OpenShift Container Platform 4 | Affected | No fix yet |
| Red Hat OpenShift GitOps | Affected | No fix yet |
| Red Hat OpenShift Virtualization 4 | Affected | No fix yet: Fix deferred |
| Red Hat Openshift Container Storage 4 | Affected | No fix planned: Out of support scope |
| Red Hat Openshift Data Foundation 4 | Affected | No fix yet |
| Red Hat Quay 3 | Affected | No fix yet |
| cert-manager Operator for Red Hat OpenShift | Affected | No fix planned: Will not fix |
| RHODF 4.13 for RHEL 9 | Fixed | RHSA-2023:3742 |
| Red Hat OpenShift Container Platform 4.12 | Fixed | RHSA-2022:7398, RHSA-2023:0569, RHSA-2023:0570, RHSA-2023:3615 |
| Red Hat OpenShift Container Platform 4.13 | Fixed | RHSA-2023:1326 |
Not affected: 12 products
- Ironic content for Red Hat OpenShift Container Platform 4.12
- Node Maintenance Operator
- OpenShift Developer Tools and Services
- OpenShift Service Mesh 2
- RHODF 4.13 for RHEL 9
- Red Hat Advanced Cluster Management for Kubernetes 2
- Red Hat OpenShift Container Platform 4
- Red Hat OpenShift Container Platform 4.12
- Red Hat OpenShift Container Platform 4.13
- Red Hat OpenStack Platform 16.1
- Red Hat OpenStack Platform 16.2
- Red Hat Openshift Data Foundation 4
Timeline
- 2026-10-02 Threatist record created from CVE-2021-4235
- 2026-10-03 Alias added: GHSA-r88r-gmrh-7j83
References
More Yaml Project Yaml vulnerabilities
- TI-2023-02110 Uncaught Exception in eemeli/yaml CVSS 3.1HIGH 7.5
- TI-2022-11545 An issue in the Unmarshal function in Go-Yaml v3 causes the program to crash when… CVSS 3.1HIGH 7.5
- TI-2022-02826 Excessive resource consumption in gopkg.in/yaml.v2 CVSS 3.1HIGH 7.5
Sources
- CVE-2021-4235 · CVE Program
- CVE-2021-4235 · NVD
- FIRST EPSS
- GHSA-r88r-gmrh-7j83 · GitHub Advisory Database · CC BY 4.0
- CVE-2021-4235 · 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