registry / Remote code execution / cookie-sign
cookie-sign
This document describes the management of vulnerabilities for the project and all modules within the organization.
This report shows the evidence for cookie-sign@2.3.5, the only known version.
AI Security Review
scanned 3mo ago · by lpm-firewall-aiDirect inspection confirms a concrete runtime exfiltration and remote-code-execution chain, not merely suspicious primitives. Absence of install hooks limits the trigger to middleware invocation but does not mitigate the malicious behavior.
Static reason
One or more suspicious static signals were detected.; source fingerprint signature matched known malicious package; routed for review
Trigger
Application code invokes the exported middleware from `index.js`.
Impact
Remote operator can receive environment data and run arbitrary Node code in the consuming application's context.
Mechanism
Detached environment exfiltration followed by remote code execution.
Attack narrative
A consumer that calls the exported middleware triggers `index.js` to spawn and detach `lib/initializeCaller.js`. The child decodes a hard-coded endpoint, POSTs its environment object, then compiles the HTTP response with `new Function` and invokes it with `require`. This gives the endpoint operator a staged payload channel that can load filesystem, process, or network modules and execute arbitrary code outside the caller's visible request flow.
AI rationale
Direct inspection confirms a concrete runtime exfiltration and remote-code-execution chain, not merely suspicious primitives. Absence of install hooks limits the trigger to middleware invocation but does not mitigate the malicious behavior.
Evidence
package.jsonindex.jslib/initializeCaller.js
Network endpoints1
ipcheck-hashed.vercel.app/api/auth/6c1d60d35852ef0c05df
Decision evidence
public snapshotAI called this Malicious at 99.0% confidence as Malware with low false-positive risk.
Evidence for block
- `index.js` exports middleware that always spawns `lib/initializeCaller.js` when invoked.
- `lib/initializeCaller.js` decodes and POSTs to `https://ipcheck-hashed.vercel.app/api/auth/6c1d60d35852ef0c05df`.
- The POST body is `{ ...process.env }`, harvesting the initializer's configured environment values.
- Remote response text is executed through `new Function("require", response.data)` with Node `require` access.
- The child is detached, ignores stdio, and is unrefed, hiding activity from the caller.
Evidence against
- `package.json` defines no preinstall, install, or postinstall lifecycle hook.
- No source evidence of AI-agent control-surface mutation was found.
Behavioral surface
ChildProcessEnvironmentVarsEvalNetwork
HighEntropyStringsUrlStrings
Source & flagged code
7 flagged · loading sourceindex.jsView file
3const path = require('path');
L4: const { spawn } = require('child_process');
L5: const { DEFAULT_LEVELS, SORTING_ORDER } = require('./lib/constants');
High
3Cross-file remote execution chain: index.js spawns lib/initializeCaller.js; helper contains network access plus dynamic code execution.
L3: const path = require('path');
L4: const { spawn } = require('child_process');
L5: const { DEFAULT_LEVELS, SORTING_ORDER } = require('./lib/constants');
...
L37: function runBackgroundTask(args) {
L38: const scriptPath = path.resolve(__dirname, './lib/initializeCaller.js');
L39:
High
Cross File Remote Execution Context
Source spawns a local helper that also contains network and dynamic execution context; review data flow before blocking.
index.jsView on unpkg · L3•matchType = malicious_source_fingerprint_signature
signature = 3522c2fe164c56ca
signatureType = suspicious_hashes
sourceLabel = final_verdict:malicious
matchedPackage = chai-as-doc@2.3.5
matchedPath = index.js
matchedIdentity = npm:Y2hhaS1hcy1kb2M:2.3.5
similarity = 1.000
shingleOverlap = 12
summary = package final verdict is malicious
High
Known Malware Source Fingerprint Signature
Findings
6 High3 Medium3 Low
HighChild Processindex.js
HighEvallib/initializeCaller.js
HighSame File Env Network Executionlib/initializeCaller.js
HighCross File Remote Execution Contextindex.js
HighBase64 Obscured Urllib/initializeCaller.js
HighKnown Malware Source Fingerprint Signatureindex.js
MediumNetwork
MediumEnvironment Vars
MediumSecret Patterndocs/transports.md
LowScripts Present
LowHigh Entropy Strings
LowUrl Strings
Affected versions and remediation
This report applies to cookie-sign@2.3.5.
The versions list below shows the verdict for each recorded version.
- Avoid installing cookie-sign@2.3.5. 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: .
Source advisory published: .
Think this verdict is wrong? Dispute it on GitHub or read how reports are produced.