Capsule
CVE-2023-46254
MEDIUM
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A01:2025 - Broken Access Control
ASVS 5.0
V14 - Data Protection Data exposure prevention
MITRE ATT&CK
2 techniques across 2 tactics: Collection, Discovery The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Impact | CVSS score of 4.3 (MEDIUM). Attack characteristics: network attack vector, low complexity, low privileges required, no user interaction not required. |
| Exploit ScenarioDerived | A remote attacker could access sensitive data that should not be disclosed by sending crafted requests to the affected application. |
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Alert meAnalysisAI
capsule-proxy is a reverse proxy for Capsule kubernetes multi-tenancy framework. Rated medium severity (CVSS 4.3), this vulnerability is remotely exploitable, low attack complexity. This Exposure of Sensitive Information vulnerability could allow attackers to access sensitive data that should not be disclosed.
RemediationAI
A vendor patch is available. Apply the latest security update as soon as possible. Minimize information in error messages, implement proper access controls, encrypt sensitive data at rest and in transit.
Affected Packages
Source: OSV (Open Source Vulnerabilities)
Affects your stack
Affects 2 packages in go
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
This vulnerability is classified as Exposure of Sensitive Information (CWE-200), which allows attackers to access sensitive data that should not be disclosed. capsule-proxy is a reverse proxy for Capsule kubernetes multi-tenancy framework. A bug in the RoleBinding reflector used by capsule-proxy gives ServiceAccount tenant owners the right to list Namespaces of other tenants backed by the same owner kind and name. For example consider two tenants solar and wind. Tenant solar, owned by a ServiceAccount named tenant-owner in the Namespace solar. Tenant wind, owned by a ServiceAccount named tenant-owner in the Namespace wind. The Tenant owner solar would be able to list the namespaces of the Tenant wind and vice-versa, although this is not correct. The bug introduces an exfiltration vulnerability since allows the listing of Namespace resources of other Tenants, although just in some specific conditions: 1. capsule-proxy runs with the --disable-caching=false (default value: false) and 2. Tenant owners are ServiceAccount, with the same resource name, but in different Namespaces. This vulnerability doesn't allow any privilege escalation on the outer tenant Namespace-scoped resources, since the Kubernetes RBAC is enforcing this. This issue has been addressed in version 0.4.5. Users are advised to upgrade. There are no known workarounds for this vulnerability. Affected products include: Clastix Capsule, Clastix Capsule-Proxy. Version information: version 0.4.5..
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Severity by source
AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionNVD
capsule-proxy is a reverse proxy for Capsule kubernetes multi-tenancy framework. A bug in the RoleBinding reflector used by capsule-proxy gives ServiceAccount tenant owners the right to list Namespaces of other tenants backed by the same owner kind and name. For example consider two tenants solar and wind. Tenant solar, owned by a ServiceAccount named tenant-owner in the Namespace solar. Tenant wind, owned by a ServiceAccount named tenant-owner in the Namespace wind. The Tenant owner solar would be able to list the namespaces of the Tenant wind and vice-versa, although this is not correct. The bug introduces an exfiltration vulnerability since allows the listing of Namespace resources of other Tenants, although just in some specific conditions: 1. capsule-proxy runs with the --disable-caching=false (default value: false) and 2. Tenant owners are ServiceAccount, with the same resource name, but in different Namespaces. This vulnerability doesn't allow any privilege escalation on the outer tenant Namespace-scoped resources, since the Kubernetes RBAC is enforcing this. This issue has been addressed in version 0.4.5. Users are advised to upgrade. There are no known workarounds for this vulnerability.
Threat Intelligence Overview
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Privilege escalation occurs when an attacker leverages flaws in access control mechanisms to gain permissions beyond what they were originally granted.
Information disclosure occurs when an application unintentionally exposes sensitive data that aids attackers in reconnaissance or directly compromises security.
Affected Products (CPE)NVD
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Capsule 0.13.0 through 0.13.6 accepts a malformed ForbiddenAnnotations.Regex on Tenant updates because the update webhoo
Capsule's node admission webhook can be crashed cluster-wide by a Cluster Admin who stores a malformed regular expressio
Privilege escalation in Capsule (Kubernetes multi-tenancy framework) versions 0.13.0-0.13.7 allows authenticated Tenant
Capsule is a multi-tenancy and policy-based framework for Kubernetes. Rated high severity (CVSS 8.8), this vulnerability
NVD
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