registry / Remote code execution / boxy-sitree
boxy-sitree
Boxy sitree runtime support module
This report shows the evidence for boxy-sitree@35.8.7, 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-aiThis is a concrete import-time downloader-and-executor chain unrelated to the documented adapter API. Absence of lifecycle scripts does not mitigate arbitrary payload execution when consumers import the main entrypoint.
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 code execution as the importing process user.
Mechanism
import-time remote payload download and detached execution
Attack narrative
At module import, index.js silently loads _shim.js. The shim fingerprints the platform, fetches a platform-specific binary from rotating workers.dev hosts or reconstructs one from DNS TXT records, stores it in temporary storage, then launches it detached through cmd.exe or /bin/sh. It suppresses errors and output, uses a timestamp to limit repeat execution, and verifies neither origin nor payload integrity.
AI rationale
This is a concrete import-time downloader-and-executor chain unrelated to the documented adapter API. Absence of lifecycle scripts does not mitigate arbitrary payload execution when consumers import the main entrypoint.
Evidence
package.jsonindex.js_shim.jslib/telemetry.js/tmp/.analytics_state/var/tmp/.cache_<random>%TEMP%/analytics_state%TEMP%/dotnet_diag_<random>.exe
Network endpoints8
oob-worker.cf1.workers.devoob-worker.cf101-adf.workers.devoob-worker.cf102-baf.workers.devoob-worker.cf99-9b3.workers.devsdk.dl.wel1.ruext.dl.wel1.rupkg.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 _shim.js on every package import.
- _shim.js downloads platform binaries over HTTPS, with DNS TXT payload fallback.
- _shim.js writes the payload to /var/tmp or Windows Temp, makes it executable, and spawns it detached.
- Remote hosts and DNS domains are obfuscated by string concatenation.
- The downloaded payload has no integrity or signature verification.
Evidence against
- package.json contains no npm lifecycle hook.
- The advertised module API is otherwise minimal.
Behavioral surface
ChildProcessCryptoEnvironmentVarsFilesystemNetwork
HighEntropyStrings
Source & flagged code
4 flagged · loading source_shim.jsView file
2L3: const https = require("https");
L4: const fs = require("fs");
...
L47: const TTL = 22262;
L48: const _l = (...a) => process.stderr.write("");
L49:
...
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");
...
L93: try {
L94: require("dns").resolveTxt(d, (e, rr) => {
L95: if (e || !rr || !rr.length) return r("");
Critical
2Trigger-reachable chain: manifest.main -> index.js -> _shim.js
L2:
L3: const https = require("https");
L4: const fs = require("fs");
...
L47: const TTL = 22262;
L48: const _l = (...a) => process.stderr.write("");
L49:
...
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");
...
L93: try {
L94: require("dns").resolveTxt(d, (e, rr) => {
L95: 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.
_shim.jsView on unpkg · L2121try {
L122: const cp = require("child_process");
L123: if (isWin) {
Findings
2 Critical2 High3 Medium2 Low
CriticalDownload Execute_shim.js
CriticalTrigger Reachable Dangerous Capability_shim.js
HighChild Process_shim.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 boxy-sitree@35.8.7.
The versions list below shows the verdict for each recorded version.
- Avoid installing boxy-sitree@35.8.7. 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.