Home/CVE/Capsule is a multi-tenancy and policy-based framework for Kubernetes. To defend against namespace hijacking achieved thr
CVE
CVE-2026-30963
Capsule is a multi-tenancy and policy-based framework for Kubernetes. To defend against namespace hijacking achieved thr
Capsule is a multi-tenancy and policy-based framework for Kubernetes. To defend against namespace hijacking achieved through update/patch operations on namespaces, Capsule uses a webhook to validate update requests targeting namespaces. However, in Kubernetes, the namespace/finalize and namespace/status subresource APIs can also modify various fields of a namespace, including the metadata field.
Prior to version 0.13.0, the webhook does not define interception rules for these subresources. As a result, if a tenant administrator has permission to modify namespace/status or namespace/finalize, they can successfully perform namespace hijacking. Version 0.13.0 fixes the issue.
Another mitigation is to add two subresources (namespaces and snamespaces/status with namespace/finalize within it) to the resources list in the ValidatingWebhookConfiguration rules.
LOW · CVSS 3.9
EPSS 0.00084
Schedule remediation
- Public exploit or PoC is available
Sigma rules0
YARA rules0
Look this up elsewhere - one-click external pivots
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How to read a CVE - triage first, then detect and patch
This page is every public fact about CVE-2026-30963, cross-linked. Its job is to answer one question fast - does this need my attention now? - and then hand you the two things you do about it. Here is how an analyst reads it.
Triage: should I act now? Four signals, and they are not interchangeable:
CVSSseverity - how bad it is IF exploited, 0-10. A high CVSS alone is not urgency; a flaw can be a perfect 10 and never actually be attacked.
EPSSprobability - a model’s estimate of the chance it is exploited in the next 30 days, 0-1. This is the “will it actually happen” signal.
CISA KEVconfirmed - it is being exploited in the wild right now. The strongest signal on the page; KEV beats any score.
Weaponisedavailability - public exploits / PoCs, and especially Metasploit modules rated Excellent / Great. Reliable, packaged exploit code means low-skill attackers can use it today.
How they combine: KEV, or a dependable Metasploit module, means patch now regardless of CVSS. High CVSS + low EPSS + no exploit is real but not an emergency - schedule it. Low CVSS but KEV-listed still gets patched now. The verdict above already weighed these for you; this is how it got there.
Then what - two workflows:
Detectwhen you cannot patch today, follow this CVE to the ATT&CK techniques it enables, then Build a SIEM detection (the green button) - author a rule, test it in Atomic, deploy it. That buys visibility while the patch waits.
PatchAffected products / packages tell you if you are exposed; Fixed versions by distribution and Vendor advisories give the exact version that closes it.
Reading order for the panels below: verdict + badges, then Public exploits / Metasploit (is it weaponised), then ATT&CK techniques + Sigma / IDS rules (can I detect it), then Affected products / packages + Fixed versions (am I exposed, what patches it), then Threat actors / IOCs (who uses it), then Scoring & timeline / references (the evidence).
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ATT&CK techniques
8Techniques this CVE enables - linked via CWECAPECATT&CK. High◆ = named directly in ATT&CK or Nuclei templates.
T1027 · Obfuscated Files or Information T1036.001 · Invalid Code Signature T1078 · Valid Accounts T1539 · Steal Web Session Cookie T1553.002 · Code Signing T1562.003 · Impair Command History Logging T1574.006 · Dynamic Linker Hijacking T1574.007 · Path Interception by PATH Environment Variable
▤ Build a SIEM detection for these techniques
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CAPEC attack patterns
12Attack patterns this CVE enables - the bridge from weakness to ATT&CK technique.
CAPEC-CAPEC-10 · Buffer Overflow via Environment Variables CAPEC-CAPEC-101 · Server Side Include (SSI) Injection CAPEC-CAPEC-104 · Cross Zone Scripting CAPEC-CAPEC-108 · Command Line Execution through SQL Injection CAPEC-CAPEC-109 · Object Relational Mapping Injection CAPEC-CAPEC-110 · SQL Injection through SOAP Parameter Tampering CAPEC-CAPEC-120 · Double Encoding CAPEC-CAPEC-13 · Subverting Environment Variable Values CAPEC-CAPEC-135 · Format String Injection CAPEC-CAPEC-136 · LDAP Injection CAPEC-CAPEC-14 · Client-side Injection-induced Buffer Overflow CAPEC-CAPEC-153 · Input Data Manipulation
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Weakness Classification
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Affected Products & Versions
1projectcapsule capsule< 0.13.0
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Affected Packages
1Language-ecosystem packages (from OSV) tied to this CVE, with the version that fixes it - the dependency-level detail NVD doesn’t carry.
Go
github.com/projectcapsule/capsule
LOW
fixed in 0.13.0
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Public Exploits & PoCs
2These PoC and exploit links come from public sources and are not verified to be safe or functional. Review the code before running anything, and treat unverified entries as untrusted.
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Scoring & Timeline
3.9
LOW · CVSS v3.1 · [email protected]
Attack Vector
Network
Adjacent
Local
Physical
Attack Complexity
Low
High
Privileges Required
None
Low
High
User Interaction
None
Required
Scope
Unchanged
Changed
Confidentiality
None
Low
High
Integrity
None
Low
High
Availability
None
Low
High
SSVC triage · cisa-vulnrichment
Exploitation
poc
Automatable
no
Technical impact
partial
SSVC asks the questions that actually drive patch urgency: is it being exploited, can attacks be automated, and how total is the impact.
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References & Sources
1Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.