registry / AI-agent control-surface risk / open-walnut / 0.5.1

open-walnut@0.5.1

Personal AI powered by Claude — task management, Claude Code sessions, memory system, and web UI

AI Security Review

scanned 13d ago · by lpm-firewall-ai

The automatic postinstall modifies a foreign AI-agent control surface by removing a safety-related system reminder. The version and context checks limit where the patch applies but do not establish user consent.

Static reason

One or more suspicious static signals were detected.; source matched previously finalized malicious package; routed for review

Trigger

Installing open-walnut through npm invokes its postinstall hook.

Impact

The modified SDK loses that reminder in its agent instructions, changing a foreign AI-agent control surface without a user consent guard.

Mechanism

The hook resolves the SDK installation, verifies a matching patch version and source context, then replaces the targeted SDK text in cli.js.

Policy narrative

During npm installation, the package's postinstall hook finds the installed Claude Agent SDK and applies a shipped patch to its cli.js. The patch removes an instruction about considering whether read files are malware and analyzing malware safely. The hook checks the SDK version and expected patch context, but source inspection shows no user consent guard for modifying this other package's agent instructions.

AI rationale

Evidence

package.jsonscripts/postinstall.mjspatches/@anthropic-ai+claude-agent-sdk+0.2.50.patch

Decision evidence

public snapshot

AI identified this as a dangerous AI-agent capability at 98.0% confidence with low false-positive risk.

Evidence for policy risk

npm install automatically runs scripts/postinstall.mjs.
The published-package postinstall locates the installed Claude Agent SDK and checks the patch version and context before editing it.
The postinstall overwrites the SDK's cli.js with patched content.
The shipped patch removes an SDK system reminder about analyzing potentially malicious files.

Evidence against

The SDK edit is version- and context-checked and skips when already applied or when the expected context is absent.

Behavioral surface

Source

ChildProcessCryptoDynamicRequireEnvironmentVarsEvalFilesystemNativeBindingsNetworkShellWebSocket

Supply chain

HighEntropyStringsMinifiedPossibleObfuscationUrlStrings

ManifestNo manifest risk signals triggered.

Source & flagged code

17 flagged

package.jsonView file

•scripts.postinstall = node scripts/postinstall.mjs

High

Install Time Lifecycle Scripts

Package defines install-time lifecycle scripts.

package.jsonView on unpkg

•scripts.postinstall = node scripts/postinstall.mjs

Medium

Ambiguous Install Lifecycle Script

Install-time lifecycle script is not statically allowlisted and needs review.

package.jsonView on unpkg

dist/plugin-store/walnut-rhythm/dist/server.mjsView file

7// plugin-store/walnut-rhythm/src/server/exec.ts L8: import { execFile } from "node:child_process"; L9: var MAX_BUFFER = 1024 * 1024;

High

Child Process

Package source references child process execution.

dist/plugin-store/walnut-rhythm/dist/server.mjsView on unpkg · L7

dist/workers/git-compaction-worker.jsView file

1234var NETWORK_GIT_RE = /^(?:clone|fetch|pull|push|ls-remote)\b/; L1235: var execAsync = promisify2(exec); L1236: function credentialGuardArgs(cwd) {

High

Shell

Package source references shell execution.

dist/workers/git-compaction-worker.jsView on unpkg · L1234

dist/web/static/assets/jszip.min-DIXBurLY.jsView file

11*/var zt;function Ot(){return zt||(zt=1,(function(yt,Rt){(function(b){yt.exports=b()})(function(){return(function b(U,k,l){function o(_,y){if(!k[_]){if(!U[_]){var p=typeof vt=="fun... L12: \0`,G+=l(E,2),G+=D.magic,G+=l(v,2),G+=l(S,2),G+=l(V.crc32,4),G+=l(V.compressedSize,4),G+=l(V.uncompressedSize,4),G+=l(L.length,2),G+=l(T.length,2),{fileRecord:p.LOCAL_FILE_HEADER+G...

Low

Eval

Package source references a known benign dynamic code generation pattern.

dist/web/static/assets/jszip.min-DIXBurLY.jsView on unpkg · L11

bin/open-walnut.jsView file

63} L64: import(entryPath.href).catch((err) => { L65: process.stderr.write(`walnut: cannot load ${entry}: ${err && err.message ? err.message : err}\n`);

Medium

Dynamic Require

Package source references dynamic require/import behavior.

bin/open-walnut.jsView on unpkg · L63

dist/daemon-binaries/daemon-service-cli.cjsView file

1var L4=Object.create;var{getPrototypeOf:P4,defineProperty:S0,getOwnPropertyNames:i5,getOwnPropertyDescriptor:O4}=Object,d5=Object.prototype.hasOwnProperty;var v=(J,X,Z)=>{Z=J!=null... L2: `).join(`\r ... L6: \r L7: `+Z)}function _0(J,X,Z,$,K,Q){if(J.listenerCount("wsClientError")){let V=Error(K);Error.captureStackTrace(V,_0),J.emit("wsClientError",V,Z,X)}else u0(Z,$,K,Q)}});var SJ={};x4(SJ,{r... L8: `)}function $0(J){return J.replace(/&/g,"&").replace(/</g,"<").replace(/>/g,">").replace(/"/g,""").replace(/'/g,"'")}function J4(J,X){let Z=J==="linux"?/^ExecSt...

High

Same File Env Network Execution

A single source file combines environment access, network access, and code or shell execution; review context before blocking.

dist/daemon-binaries/daemon-service-cli.cjsView on unpkg · L1

High

Command Output Exfiltration

Source combines command execution, command-output handling, and outbound requests; review data flow before blocking.

dist/daemon-binaries/daemon-service-cli.cjsView on unpkg · L1

dist/daemon-binaries/dtach-darwin-arm64View file

•path = dist/daemon-binaries/dtach-darwin-arm64 kind = native_binary sizeBytes = 52384 magicHex = [redacted]

Medium

Ships Native Binary

Package ships native binary artifacts.

dist/daemon-binaries/dtach-darwin-arm64View on unpkg

dist/data/skills/walnut-register-repo/scripts/validate-repo.pyView file

•path = dist/data/skills/walnut-register-repo/scripts/validate-repo.py kind = build_helper sizeBytes = 5994 magicHex = [redacted]

Medium

Ships Build Helper

Package ships non-JavaScript build or shell helper files.

dist/data/skills/walnut-register-repo/scripts/validate-repo.pyView on unpkg

dist/web/server.jsView file

•path = dist/web/server.js kind = oversized_source_file sizeBytes = 8909712 magicHex = [redacted]

Medium

Oversized Source File

Package contains source files above the normal full-analysis size ceiling.

dist/web/server.jsView on unpkg

dist/cli.jsView file

•path = dist/cli.js kind = oversized_cli_entrypoint sizeBytes = 9082335 magicHex = [redacted]

Medium

Oversized Cli Entrypoint

Package contains an oversized executable-looking CLI entrypoint.

dist/cli.jsView on unpkg

dist/cli-fast.jsView file

•stage = ast_semantic_analysis; reason = ast_alias_growth_limit_exceeded; limitedFiles = 7

High

Semantic Analysis Limited

A bounded semantic-analysis stage reached its safety limit; remaining detectors completed, but this package requires AI review.

dist/cli-fast.jsView on unpkg

dist/daemon-binaries/acp-worker.jsView file

•matchType = normalized_sha256 matchedPackage = open-walnut@0.4.5 matchedPath = dist/daemon-binaries/acp-worker.js matchedIdentity = npm:b3Blbi13YWxudXQ:0.4.5 similarity = 1.000 summary = normalized source hash matched finalized malicious source

High

Known Malware Source Similarity

Source file is highly similar to a previously finalized malicious package; route for source-aware review.

dist/daemon-binaries/acp-worker.jsView on unpkg

dist/integrations/walnut-time/dist/web.mjsView file

•matchType = normalized_sha256 matchedPackage = open-walnut@0.4.5 matchedPath = dist/integrations/walnut-time/dist/web.mjs matchedIdentity = npm:b3Blbi13YWxudXQ:0.4.5 similarity = 1.000 summary = normalized source hash matched finalized malicious source

High

Known Malware Source Similarity

Source file is highly similar to a previously finalized malicious package; route for source-aware review.

dist/integrations/walnut-time/dist/web.mjsView on unpkg

dist/web/static/assets/vbscript-BuJXcnF6.jsView file

•matchType = normalized_sha256 matchedPackage = open-walnut@0.4.5 matchedPath = dist/web/static/assets/vbscript-BuJXcnF6.js matchedIdentity = npm:b3Blbi13YWxudXQ:0.4.5 similarity = 1.000 summary = normalized source hash matched finalized malicious source

High

Known Malware Source Similarity

Source file is highly similar to a previously finalized malicious package; route for source-aware review.

dist/web/static/assets/vbscript-BuJXcnF6.jsView on unpkg

Source & flagged code

17 flagged · loading source

package.jsonView file

•scripts.postinstall = node scripts/postinstall.mjs

High

Install Time Lifecycle Scripts

Package defines install-time lifecycle scripts.

package.jsonView on unpkg

•scripts.postinstall = node scripts/postinstall.mjs

Medium

Ambiguous Install Lifecycle Script

Install-time lifecycle script is not statically allowlisted and needs review.

package.jsonView on unpkg

dist/plugin-store/walnut-rhythm/dist/server.mjsView file

7// plugin-store/walnut-rhythm/src/server/exec.ts L8: import { execFile } from "node:child_process"; L9: var MAX_BUFFER = 1024 * 1024;

High

Child Process

Package source references child process execution.

dist/plugin-store/walnut-rhythm/dist/server.mjsView on unpkg · L7

Findings

9 High9 Medium7 Low

HighInstall Time Lifecycle Scriptspackage.json

HighChild Processdist/plugin-store/walnut-rhythm/dist/server.mjs

HighShelldist/workers/git-compaction-worker.js

HighSame File Env Network Executiondist/daemon-binaries/daemon-service-cli.cjs

HighCommand Output Exfiltrationdist/daemon-binaries/daemon-service-cli.cjs

HighSemantic Analysis Limiteddist/cli-fast.js

HighKnown Malware Source Similaritydist/daemon-binaries/acp-worker.js

HighKnown Malware Source Similaritydist/integrations/walnut-time/dist/web.mjs

HighKnown Malware Source Similaritydist/web/static/assets/vbscript-BuJXcnF6.js

MediumAmbiguous Install Lifecycle Scriptpackage.json

Medium

Affected versions and remediation

This report applies to open-walnut@0.5.1.

See all versions of open-walnut for other recorded verdicts.

Avoid installing open-walnut@0.5.1. Remove it from direct dependencies and check your lockfile for transitive copies.
Choose an independently verified alternative or release. This report does not establish that other versions are safe.
If this version ran, investigate the affected machine and build environment. Rotate credentials it could access and rebuild from a trusted environment.

Evidence last updated: 2026-10-09 18:35:16.380Z (UTC).

Think this verdict is wrong? Dispute it on GitHub or read how reports are produced.

AI Security Review

Decision evidence

Source & flagged code

Source & flagged code

Findings

Affected versions and remediation

Related packages

Other AI-agent control-surface risk packages

Runtime surface

Behavioral surface

Related packages

Other AI-agent control-surface risk packages

Source & flagged code