runcastle@1.3.5
Burn tickets into shipped features with Claude Code.
AI Security Review
scanned 5d ago · by lpm-firewall-aiThe suspicious routing hints were not confirmed in the inspected source: the agent server URL is localhost, and the Codex auth file is copied into a session home for the Codex runtime. The reviewed download command installs Bun from its official host as part of the sandbox image build.
Static reason
One or more suspicious static signals were detected.; previous stored version diff introduced dangerous source
Trigger
An explicit runcastle session launch prepares the agent runtime; the official Bun installer runs when building the sandbox image.
Impact
No unauthorized credential redirection, data exfiltration, or unrelated execution was established.
Mechanism
Session setup provides the local server URL and, for Codex, copies the user's existing auth.json into the session home. The Dockerfile installs Bun from bun.sh.
AI rationale
The suspicious routing hints were not confirmed in the inspected source: the agent server URL is localhost, and the Codex auth file is copied into a session home for the Codex runtime. The reviewed download command installs Bun from its official host as part of the sandbox image build.
Evidence
auth.json
Network endpoints2
localhostbun.sh
Decision evidence
public snapshotAI called this Clean at 84.0% confidence as Benign with low false-positive risk.
Evidence for AI clean decision
- The manifest describes runcastle as a Claude Code workflow tool and exposes its CLI through bin/runcastle.js.
- The Claude runtime receives the local runcastle server URL in its environment.
- The Codex runtime copies the existing Codex auth.json into the session home for the Codex CLI.
- The sandbox image installs Bun from its official bun.sh host.
Evidence against
- The inspected source defines the agent server URL as localhost.
- The reviewed credential handling is tied to preparing a Codex session, and no fixed unofficial credential gateway was found in the inspected source.
Behavioral surface
ChildProcessCryptoDynamicRequireEnvironmentVarsFilesystemNetworkShellWebSocket
HighEntropyStringsMinifiedPossibleObfuscationUrlStrings
Source & flagged code
8 flaggedbin/runcastle.jsView file
•matchType = previous_version_dangerous_delta
matchedPackage = runcastle@1.2.11
matchedIdentity = npm:cnVuY2FzdGxl:1.2.11
similarity = 0.600
summary = stored previous version shares package body but lacks this dangerous source file
Critical
Previous Version Dangerous Delta
This package version adds a dangerous source file absent from the previous stored version; route for source-aware review.
bin/runcastle.jsView on unpkg1238// src/pty/kill-tree.ts
L1239: import { spawn } from "child_process";
L1240: function taskkillTree(pid) {
High
Child Process
Package source references child process execution.
bin/runcastle.jsView on unpkg · L12381170if (/\.(cmd|bat)$/i.test(resolved)) {
L1171: return { file: process.env.ComSpec ?? "cmd.exe", args: ["/c", resolved, ...args] };
L1172: }
High
Findings
1 Critical5 High4 Medium4 Low
CriticalPrevious Version Dangerous Deltabin/runcastle.js
HighChild Processbin/runcastle.js
HighShellbin/runcastle.js
HighSame File Env Network Executionbin/runcastle.js
HighCredential Redirect Persistenceindex.js
HighCross File Remote Execution Contextbin/runcastle.js
MediumDynamic Requirepty-host.cjs
MediumNetwork
MediumEnvironment Vars
MediumStructural Risk Force Deep Review
LowWeak Cryptobin/runcastle.js
LowFilesystem
LowHigh Entropy Strings
LowUrl Strings
Affected versions and remediation
This report applies to runcastle@1.3.5.
See all versions of runcastle for other recorded verdicts.
- Review the evidence and your use of runcastle@1.3.5 before allowing it. Restrict the permissions described in this report.
- Choose an independently verified alternative or release. This report does not establish that other versions are safe.
Evidence last updated: .
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