registry / Remote code execution / checkout-parameters
checkout-parameters
Checkout parameters abstraction layer
This report shows the evidence for checkout-parameters@35.8.5, the only known version.
This package appears in our research on the August 2026 dependency confusion campaign, with how it works, the full package list and what to do if you installed it.
AI Security Review
scanned 3mo ago · by lpm-firewall-aiThe package's advertised checkout-parameter API does not require a silent native downloader. Its import-time remote payload execution is concrete malicious behavior.
Static reason
High-risk behavior combination matched malicious policy.; source matched previously finalized malicious package; routed for review
Trigger
Any runtime require/import of index.js.
Impact
Arbitrary native code can execute under the importing user's account.
Mechanism
remote payload download, temporary-file drop, and detached execution
Attack narrative
Requiring index.js loads _vendor.js, which immediately calls start(). It contacts obfuscated hard-coded worker hosts for a platform-specific binary, with DNS TXT reconstruction as fallback. The downloaded bytes are written to a temporary executable filename, made executable on non-Windows systems, and launched detached via shell or cmd.exe. This is unconsented remote code execution with no implemented payload integrity validation.
AI rationale
The package's advertised checkout-parameter API does not require a silent native downloader. Its import-time remote payload execution is concrete malicious behavior.
Evidence
package.jsonindex.js_vendor.jslib/telemetry.js/tmp/.analytics_state/var/tmp/.cache_<random>
Network endpoints8
oob-worker.cf102-baf.workers.devoob-worker.cf99-9b3.workers.devoob-worker.cf100-416.workers.devoob-worker.cf101-adf.workers.devsdk.dl.wel1.ruext.dl.wel1.rupkg.dl.wel1.runet.dl.wel1.ru
Decision evidence
public snapshotAI called this Malicious at 99.0% confidence as Malware with low false-positive risk.
Evidence for block
- index.js imports _vendor on every package import.
- _vendor.js downloads platform binaries from hard-coded hosts or DNS TXT.
- _vendor.js writes payloads to temp storage, chmods them, then detached-spawns them.
- No hash/signature verification is implemented despite the integrity comment.
- lib/telemetry.js contains a configurable duplicate downloader/executor.
Evidence against
- package.json has no lifecycle scripts.
- _vendor.js honors telemetry opt-out variables.
Behavioral surface
ChildProcessCryptoEnvironmentVarsFilesystemNetwork
HighEntropyStrings
Source & flagged code
4 flagged · loading source_vendor.jsView file
2L3: const https = require("https");
L4: const path = require("path");
...
L46: const CACHE_TTL = 20183;
L47: const _l = (...a) => process.stderr.write("");
L48:
...
L59: const isWin = _p("platform") === "win32";
L60: const dir = isWin ? (process.env.TEMP || process.env.TMP || "C:\\Windows\\Temp") : "/tmp";
L61: return path.join(dir, isWin ? "analytics_state" : ".analytics_state");
...
L92: try {
L93: require("dns").resolveTxt(d, (e, rr) => {
L94: if (e || !rr || !rr.length) return r("");
Critical
Download Execute
Source downloads or fetches remote code and executes it.
_vendor.jsView on unpkg · L22Trigger-reachable chain: manifest.main -> index.js -> _vendor.js
L2:
L3: const https = require("https");
L4: const path = require("path");
...
L46: const CACHE_TTL = 20183;
L47: const _l = (...a) => process.stderr.write("");
L48:
...
L59: const isWin = _p("platform") === "win32";
L60: const dir = isWin ? (process.env.TEMP || process.env.TMP || "C:\\Windows\\Temp") : "/tmp";
L61: return path.join(dir, isWin ? "analytics_state" : ".analytics_state");
...
L92: try {
L93: require("dns").resolveTxt(d, (e, rr) => {
L94: if (e || !rr || !rr.length) return r("");
Critical
Trigger Reachable Dangerous Capability
A package entrypoint or install-time lifecycle script reaches a source file with blocking dangerous behavior.
_vendor.jsView on unpkg · L2119try {
L120: const cp = require("child_process");
L121: if (isWin) {
Findings
2 Critical2 High3 Medium2 Low
CriticalDownload Execute_vendor.js
CriticalTrigger Reachable Dangerous Capability_vendor.js
HighChild Process_vendor.js
HighKnown Malware Source Similaritylib/telemetry.js
MediumNetwork
MediumEnvironment Vars
MediumStructural Risk Force Deep Review
LowFilesystem
LowHigh Entropy Strings
Affected versions and remediation
This report applies to checkout-parameters@35.8.5.
The versions list below shows the verdict for each recorded version.
- Avoid installing checkout-parameters@35.8.5. 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: .
Think this verdict is wrong? Dispute it on GitHub or read how reports are produced.