registry / Typosquat / @pilllesss/yorn / 1.0.159

@pilllesss/yorn@1.0.159

AI Security Review

scanned 2mo ago · by lpm-firewall-ai

This appears to be an unaffiliated republishing of a powerful coding-agent CLI, which is a meaningful supply-chain risk. The inspected source does not establish concrete malicious behavior or an install-time attack chain.

Static reason

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

Trigger

A user runs the yorn command and permits its coding-agent actions.

Impact

It has the normal high authority of a user-invoked coding agent; the publisher mismatch makes that authority risky.

Mechanism

A repackaged command-line coding agent executes runtime tools.

AI rationale

Evidence

package.jsondist/yorn.cjs

Network endpoints1

registry.npmjs.org

Decision evidence

public snapshot

AI called this Suspicious at 72.0% confidence as Dangerous Capability with medium false-positive risk.

Evidence for warning

The package is named @pilllesss/yorn, but its bundled runtime identifies its upstream repository as siwat/yorn.
The published command is a large AI coding-agent runtime with command execution and file-write capabilities.

Evidence against

The only lifecycle hook is prepublishOnly, so installation does not run package code.
Inspection did not confirm the claimed fixed credential gateway, foreign-package overwrite, or command-output exfiltration.
The inspected process and file operations are runtime CLI features rather than install-time behavior.

Behavioral surface

Source

ChildProcessCryptoDynamicRequireEnvironmentVarsFilesystemNetwork

Supply chain

HighEntropyStringsMinified

ManifestNo manifest risk signals triggered.

scanned 0 file(s), 256 KB of source

Oversized source lightweight scan

Source & flagged code

14 flagged

dist/yorn.cjsView file

22\r L23: `),n=!1,s=!1;e.on("response",e=>{let{headers:t}=e;n="chunked"===t[tHo.build(["encodi","tran","ng","sfer-"],[1,3,0,2])]&&!t[tHo.build([tHo.build(["content-","le"],[0,1]),"ngth"],[0,... L24: `)}function eZo(e){return e.map(e=>"text"===e.type?e.text:"thinking"===e.type?e.thinking:`${e.name}:${JSON.stringify(e.arguments)}`).join(`

High

Child Process

Package source references child process execution.

dist/yorn.cjsView on unpkg · L22

11${eLk(e)}`);if(null==o)throw new Il(`missing choices[${r}].tool_calls[${i}].function.arguments L12: ${eLk(e)}`);return{...a,id:l,type:s,function:{...d,name:u,arguments:o}}})}}:{...s,message:{...u,content:l,role:d,refusal:t.refusal??null},finish_reason:i,index:r,logprobs:n}}),crea... L13: Content-Disposition: form-data; name="`;return e.forEach((e,t)=>"string"==typeof e?r.push(n+Py(t)+`"\r ... L22: \r L23: `),n=!1,s=!1;e.on("response",e=>{let{headers:t}=e;n="chunked"===t[tHo.build(["encodi","tran","ng","sfer-"],[1,3,0,2])]&&!t[tHo.build([tHo.build(["content-","le"],[0,1]),"ngth"],[0,... L24: `)}function eZo(e){return e.map(e=>"text"===e.type?e.text:"thinking"===e.type?e.thinking:`${e.name}:${JSON.stringify(e.arguments)}`).join(`

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/yorn.cjsView on unpkg · L11

•Manifest-reachable source captures an API credential, sends it to a fixed unofficial gateway, and persists that redirection in agent or shell configuration. dist/yorn.cjs: `),n=!1,s=!1;e.on("response",e=>{let{headers:t}=e;n="chunked"===t[tHo.build(["encodi","tran","ng","sfer-"],[1,3,0,2])]&&!t[tHo.build([tHo.build(["content-","le"],[0,1]),"ngth"],[0,... `)}function eZb(e,t){let i=Math.min(e.length,t.length),r=0;for(;r<i&&e[r]===t[r];)r++;return r}function eZh(e,t,i,r){let n=eZc(t),s=eZs(n),l=eZs(eZo(e.content)),a=s,o=0,u=0,d=i?.se... `){return"string"==typeof e?e:e.filter(e=>"text"===e.type).map(e=>e.text).join(t)}function eZB(e,t){return Yb.Unsafe({type:"string",enum:e,...t?.description&&{description:t.descrip... --api-key <key> API key (defaults to env vars) # Print a prov

High

Credential Redirect Persistence

Manifest-reachable source sends a prompted API credential to a fixed unofficial gateway and persists the redirection.

dist/yorn.cjsView on unpkg

•Manifest-reachable source resolves another installed package, overwrites its runtime code, and injects package-defined remote behavior. dist/yorn.cjs: `)),r.push(`--${i}--`),new t(r,{type:tHo.build(["multi","-data;","part","/form"," boun","dary="],[0,2,3,1,4,5])+i})}function eL3(e){let t=e.match(/\bfilename=("(.*?)"|([^()<>@,;:\\... AZURE_OPENAI_BASE_URL - Azure OpenAI/Cognitive Services base URL (e.g. https://{resource}.openai.azure.com) YORN_SHARE_VIEWER_URL - Base URL for /share command (default: https://pi.dev/session/) `),a=t.content.some(e=>"image"===e.type),d={role:"tool",content:eMB(l.length>0?l:a?tHo.build(["ed im",tHo.build(["(see atta","ch"],[0,1]),"age)"],[1,0,2]):tHo.build(["(no ","t)",tH... </html>`}function tt3(e){return tt2({title:tHo.build(["uccess","

High

Entrypoint Foreign Package Code Overwrite

Manifest-reachable source overwrites another installed package with package-defined remote behavior.

dist/yorn.cjsView on unpkg

7`),u.push(`\r L8: `)}u.push(null)}),u}async function eDA(e,t){let i=0,r=[],n=e.getReader(),s=!1;for(;!s;){let{done:e,value:l}=await n.read();if(l&&(r.push(l),i+=l?.byteLength??0),i>=t)break;s=e}n.re... L9: ${eLk(e)}`);if(null==s)throw new Il(`missing choices[${r}].tool_calls[${i}].type ... L11: ${eLk(e)}`);if(null==o)throw new Il(`missing choices[${r}].tool_calls[${i}].function.arguments L12: ${eLk(e)}`);return{...a,id:l,type:s,function:{...d,name:u,arguments:o}}})}}:{...s,message:{...u,content:l,role:d,refusal:t.refusal??null},finish_reason:i,index:r,logprobs:n}}),crea... L13: Content-Disposition: form-data; name="`;return e.forEach((e,t)=>"string"==typeof e?r.push(n+Py(t)+`"\r ... L22: \r L23: `),n=!1,s=!1;e.on("response",e=>{let{headers:t}=e;n="chunked"===t[tHo.build(["encodi","tran

High

Command Output Exfiltration

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

dist/yorn.cjsView on unpkg · L7

2globalThis.__yorn_dynamic_import = (m) => import(m); L3: var e,t,i,r,n,s,l,a,o,u,d,c,b,h,p,m,f,g,_,y,E,S,v,A,w,T,C,I,x,R,O,k,N,D,P,M,L,F,U,B,$,j,G,q,H,W,V,Y,K,z,Q,J,X,Z,ee,et,ei,er,en,es,el,ea,eo,eu,ed,ec,eb,eh,ep,em,ef,eg,e_,ey,eE,eS,ev... L4: `),u.push(e),u.push(`\r ... L7: `),u.push(`\r L8: `)}u.push(null)}),u}async function eDA(e,t){let i=0,r=[],n=e.getReader(),s=!1;for(;!s;){let{done:e,value:l}=await n.read();if(l&&(r.push(l),i+=l?.byteLength??0),i>=t)break;s=e}n.re... L9: ${eLk(e)}`);if(null==s)throw new Il(`missing choices[${r}].tool_calls[${i}].type ... L11: ${eLk(e)}`);if(null==o)throw new Il(`missing choices[${r}].tool_calls[${i}].function.arguments L12: ${eLk(e)}`);return{...a,id:l,type:s,function:{...d,name:u,arguments:o}}})}}:{...s,message:{...u,content:l,role:d,refusal:t.

High

Cloud Metadata Access

Source reaches cloud instance metadata or link-local credential endpoints.

dist/yorn.cjsView on unpkg · L2

7Trigger-reachable command-output exfiltration chain: manifest.bin -> dist/yorn.cjs L7: `),u.push(`\r L8: `)}u.push(null)}),u}async function eDA(e,t){let i=0,r=[],n=e.getReader(),s=!1;for(;!s;){let{done:e,value:l}=await n.read();if(l&&(r.push(l),i+=l?.byteLength??0),i>=t)break;s=e}n.re... L9: ${eLk(e)}`);if(null==s)throw new Il(`missing choices[${r}].tool_calls[${i}].type ... L11: ${eLk(e)}`);if(null==o)throw new Il(`missing choices[${r}].tool_calls[${i}].function.arguments L12: ${eLk(e)}`);return{...a,id:l,type:s,function:{...d,name:u,arguments:o}}})}}:{...s,message:{...u,content:l,role:d,refusal:t.refusal??null},finish_reason:i,index:r,logprobs:n}}),crea... L13: Content-Disposition: form-data; name="`;return e.forEach((e,t)=>"string"==typeof e?r.push(n+Py(t)+`"\r ... L22: \r L23: `),n=!1,

High

Trigger Reachable Command Output Exfiltration

A manifest entrypoint or package-local install chain reaches command-output exfiltration behavior.

dist/yorn.cjsView on unpkg · L7

•stage = ast_semantic_analysis; reason = ast_path_work_budget_exceeded; limitedFiles = 1

High

Semantic Analysis Limited

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

dist/yorn.cjsView on unpkg

•matchType = normalized_sha256 matchedPackage = @pilllesss/yorn@1.0.92 matchedPath = dist/yorn.cjs matchedIdentity = npm:QHBpbGxsZXNzcy95b3Ju:1.0.92 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/yorn.cjsView on unpkg

•matchType = malicious_source_fingerprint_signature signature = 8eb5d4d2248a43c7 signatureType = suspicious_hashes sourceLabel = final_verdict:malicious matchedPackage = @pilllesss/yorn@1.0.92 matchedPath = dist/yorn.cjs matchedIdentity = npm:QHBpbGxsZXNzcy95b3Ju:1.0.92 similarity = 1.000 shingleOverlap = 2 summary = package final verdict is malicious

High

Known Malware Source Fingerprint Signature

Source fingerprint signature matches a known malicious package signature; route for source-aware review.

dist/yorn.cjsView on unpkg

1#!/usr/bin/env node L2: globalThis.__yorn_dynamic_import = (m) => import(m); L3: var e,t,i,r,n,s,l,a,o,u,d,c,b,h,p,m,f,g,_,y,E,S,v,A,w,T,C,I,x,R,O,k,N,D,P,M,L,F,U,B,$,j,G,q,H,W,V,Y,K,z,Q,J,X,Z,ee,et,ei,er,en,es,el,ea,eo,eu,ed,ec,eb,eh,ep,em,ef,eg,e_,ey,eE,eS,ev...

Medium

Dynamic Require

Package source references dynamic require/import behavior.

dist/yorn.cjsView on unpkg · L1

•path = dist/yorn.cjs kind = oversized_source_file sizeBytes = 7684704 magicHex = [redacted]

Medium

Oversized Source File

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

dist/yorn.cjsView on unpkg

•path = dist/yorn.cjs kind = oversized_cli_entrypoint sizeBytes = 7684704 magicHex = [redacted]

Medium

Oversized Cli Entrypoint

Package contains an oversized executable-looking CLI entrypoint.

dist/yorn.cjsView on unpkg

dist/skills/screenshot/scripts/take_screenshot.pyView file

•path = dist/skills/screenshot/scripts/take_screenshot.py kind = build_helper sizeBytes = 19659 magicHex = [redacted]

Medium

Ships Build Helper

Package ships non-JavaScript build or shell helper files.

dist/skills/screenshot/scripts/take_screenshot.pyView on unpkg

Source & flagged code

14 flagged · loading source

dist/yorn.cjsView file

High

Child Process

Package source references child process execution.

dist/yorn.cjsView on unpkg · L22

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/yorn.cjsView on unpkg · L11

Findings

10 High7 Medium4 Low

HighChild Processdist/yorn.cjs

HighSame File Env Network Executiondist/yorn.cjs

HighCredential Redirect Persistencedist/yorn.cjs

HighEntrypoint Foreign Package Code Overwritedist/yorn.cjs

HighCommand Output Exfiltrationdist/yorn.cjs

HighCloud Metadata Accessdist/yorn.cjs

HighTrigger Reachable Command Output Exfiltrationdist/yorn.cjs

HighSemantic Analysis Limiteddist/yorn.cjs

HighKnown Malware Source Similaritydist/yorn.cjs

HighKnown Malware Source Fingerprint Signaturedist/yorn.cjs

MediumDynamic Requiredist/yorn.cjs

MediumNetwork

Affected versions and remediation

This report applies to @pilllesss/yorn@1.0.159.

See all versions of @pilllesss/yorn for other recorded verdicts.

Review the evidence and your use of @pilllesss/yorn@1.0.159 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: 2026-08-27 02:12:15.251Z (UTC).

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