ANSI escape characters in kubectl output are not being filtered
Priority LOW 16CWE-150Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- Required
- Attack complexity
- High
- Impact type
- —
- Confidentiality · integrity · availability
- None · Low · None
- Fix status
- Partial Red Hat: 5 without a fix
Attack profile from CVSS 3.1 · CNA. Fix status from CNA, GitHub and Red Hat.
Summary
kubectl does not neutralize escape, meta or control sequences contained in the raw data it outputs to a terminal. This includes but is not limited to the unstructured string fields in objects such as Events.
Why it matters now
EPSS 0.00844 58th percentileScored 2026-11-07
Fix Partial k8s.io/kubernetes (Go): 1.26.0-alpha.3Red Hat: 5 without a fix
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Kubernetes | Kubernetes | up to 1.23.1; up to 1.22.5; up to 1.21.8; up to 1.20.14 | — | No fix listed | CNA |
| — | k8s.io/kubernetes (Go) | before 1.26.0-alpha.3 | 1.26.0-alpha.3 | Patch available | GHSA-f9jg-8p32-2f55 |
- Kubernetes VendorKubernetes Affected up to 1.23.1; up to 1.22.5; up to 1.21.8; up to 1.20.14 Fixed in — No fix listed CNA
- k8s.io/kubernetes (Go) Vendor— Affected before 1.26.0-alpha.3 Fixed in 1.26.0-alpha.3 Patch available GHSA-f9jg-8p32-2f55
CPE configurations NVD · 4
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:kubernetes:kubernetes:*:*:*:*:*:*:*:* | up to 1.25.0 | Vulnerable | Kubernetes |
| cpe:2.3:a:kubernetes:kubernetes:1.26.0:alpha0:*:*:*:*:*:* | 1.26.0 alpha0 | Vulnerable | Kubernetes |
| cpe:2.3:a:kubernetes:kubernetes:1.26.0:alpha1:*:*:*:*:*:* | 1.26.0 alpha1 | Vulnerable | Kubernetes |
| cpe:2.3:a:kubernetes:kubernetes:1.26.0:alpha2:*:*:*:*:*:* | 1.26.0 alpha2 | Vulnerable | Kubernetes |
- cpe:2.3:a:kubernetes:kubernetes:*:*:*:*:*:*:*:* Versions up to 1.25.0 Vulnerable ·Kubernetes
- cpe:2.3:a:kubernetes:kubernetes:1.26.0:alpha0:*:*:*:*:*:* Versions 1.26.0 alpha0 Vulnerable ·Kubernetes
- cpe:2.3:a:kubernetes:kubernetes:1.26.0:alpha1:*:*:*:*:*:* Versions 1.26.0 alpha1 Vulnerable ·Kubernetes
- cpe:2.3:a:kubernetes:kubernetes:1.26.0:alpha2:*:*:*:*:*:* Versions 1.26.0 alpha2 Vulnerable ·Kubernetes
Remediation
- Fix · GHSA-f9jg-8p32-2f55 k8s.io/kubernetes (Go) Fixed in 1.26.0-alpha.3 Advisory →
Vendor assessments
Red Hat
Red Hat rating: Low. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Advanced Cluster Management for Kubernetes 2 | Affected | No fix yet: Fix deferred |
| Red Hat Ansible Automation Platform 1.2 | Affected | No fix yet |
| Red Hat Ansible Tower 3 | Affected | No fix yet |
| Red Hat OpenShift Container Platform 3.11 | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift Container Platform 4 | Affected | No fix yet |
Timeline
- 2026-10-02 Threatist record created from CVE-2021-25743
- 2026-10-03 Alias added: GHSA-f9jg-8p32-2f55
References
Advisory 3
More Kubernetes vulnerabilities
- TI-2018-16130 Improper privilege management in Kubernetes CVSS 3.0CRITICAL 9.8
- TI-2019-08418 Kubernetes kubelet exposes /debug/pprof info on healthz port CVSS 3.1HIGH 8.2
- TI-2023-05086 Kubernetes - Windows nodes - Insufficient input sanitization in in-tree storage plugin leads to privilege escalation CVSS 3.1HIGH 8.8
- TI-2023-03433 Kubernetes - Windows nodes - Insufficient input sanitization leads to privilege escalation CVSS 3.1HIGH 8.8
- TI-2023-02285 Bypass of seccomp profile enforcement CVSS 3.1MEDIUM 5.5
- TI-2017-14755 Link following in Kubernetes CVSS 3.0CRITICAL 9.6
Sources
- CVE-2021-25743 · CVE Program
- CVE-2021-25743 · NVD
- FIRST EPSS
- GHSA-f9jg-8p32-2f55 · GitHub Advisory Database · CC BY 4.0
- CVE-2021-25743 · 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