CVE-2026-43991

Host command execution via substring blocklist bypass

Published May 12, 2026 · Updated May 12, 2026

OS command injection in JunoClaw plugin-shell before 0.x.y-security-1 allows local users to execute unauthorized host commands. The command-safety check compares a raw command string against an incomplete substring blocklist instead of validating the parsed executable token, so crafted arguments evade the denylist and reach the shell wrapper. Exploitation requires local access to a build exposing plugin-shell execution and the companion advisory’s path; successful use runs commands with the JunoClaw process privileges.

CVSS severityUnavailable
Unscored
EPSS probability0.17%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

OS command injection in JunoClaw plugin-shell before 0.x.y-security-1 allows local users to execute unauthorized host commands. The command-safety check compares a raw command string against an incomplete substring blocklist instead of validating the parsed executable token, so crafted arguments evade the denylist and reach the shell wrapper. Exploitation requires local access to a build exposing plugin-shell execution and the companion advisory’s path; successful use runs commands with the JunoClaw process privileges.

The record

CVE
CVE-2026-43991
Published
May 12, 2026
Updated
May 12, 2026
Vendor
Dragonmonk111
Product
JunoClaw
Classifications
T1059
Attack vector
local
Privileges
Unavailable

Timeline

How it unfolded

  1. May 12, 2026CVE publishedPublication date reported by the CVE source.
  2. May 12, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< v0.x.y-security-1

What conditions does exploitation require?

Attack vectorlocal
Required privilegesUnavailable in this record.

What is affected?

Dragonmonk111 · JunoClawversion=< v0.x.y-security-1

Published CVSS scores

No CVSS assessment is available in this record.

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1059Command and Scripting Interpreter

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo