Apache Karaf: OS Command Injection in Child-Instance Launch (instance:* / InstancesMBean) (CVE-2026-91006) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-91006

Apache Karaf: OS Command Injection in Child-Instance Launch (instance:* / InstancesMBean)

Answer in brief

CVE-2026-91006 records a Unknown severity vulnerability in Apache Karaf: OS Command Injection in Child-Instance Launch (instance:* / InstancesMBean). The current sources do not mark it as known exploited. The current feed maps Apache Software Foundation/Apache Karaf (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 28, 2026Updated Sep 28, 2026Source checked Sep 28, 2026First seen by HOL Sep 28, 2026Material review Sep 28, 2026

Upstream Advisory

Key facts

Risk: Unknown severitySource severity not reported
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Available

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps Apache Software Foundation/Apache Karaf (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
Apache Software Foundation/Apache Karafgeneric	>=0 <4.4.12	4.4.12

Recommended response

Check inventory. Check lockfiles and deployed manifests for Apache Software Foundation/Apache Karaf.
Review the reported fix. Update Apache Software Foundation/Apache Karaf to 4.4.12 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 28, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 28, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 28, 2026

Sources and claim methodology

Source referencelists.apache.org

Upstream source description

Apache Karaf's instance-management service (InstanceServiceImpl) builds the command line used to launch a child Karaf JVM by string concatenation, then executes it through /bin/sh (Unix) or cscript (Windows). The caller-supplied javaOpts value is spliced into that string unquoted. A javaOpts value containing shell metacharacters (;, |, `, $(...)) is interpreted by the shell instead of being passed to the JVM as an option, giving arbitrary OS command execution as the Karaf process user. Reachable via the shell commands instance:create, instance:start, instance:restart, instance:change-opts, and the equivalent InstanceMBean JMX operations (createInstance, startInstance, changeJavaOpts, cloneInstance). Mitigation * Set karaf.secured.command.compulsory.roles=admin in etc/system.properties to close the fail-open gap for all unconfigured command scopes. * Restrict which principals can reach instance:* commands and InstancesMBean via etc/users.properties role assignments. * Treat javaOpts passed to instance:create/instance:start/instance:change-opts/InstancesMBean as untrusted input only from fully-trusted operators.

Quoted source text, attributed separately from HOL analysis.