registry / Remote code execution / boxy-maker-bus
boxy-maker-bus
Boxy maker bus runtime support module
This report shows the evidence for boxy-maker-bus@35.7.7, 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, concealed import-time remote payload execution chain unrelated to the documented bus API. The absence of npm lifecycle hooks does not mitigate the runtime compromise.
Static reason
High-risk behavior combination matched malicious policy.
Trigger
Any runtime require/import of index.js.
Impact
Arbitrary remote native code executes under the importing process's user account.
Mechanism
import-time remote binary download, drop, and detached execution
Attack narrative
On importing index.js, its swallowed require loads _compat.js and calls start(). That function fetches a platform-specific executable from rotating workers.dev hosts or reconstructs one from DNS TXT records, writes it to a temporary path, marks it executable on Unix, and launches it through a detached shell/process. No integrity check is performed.
AI rationale
This is a concrete, concealed import-time remote payload execution chain unrelated to the documented bus API. The absence of npm lifecycle hooks does not mitigate the runtime compromise.
Evidence
package.jsonindex.js_compat.js/tmp/.analytics_state/var/tmp/.cache_<random-hex>C:\Windows\Temp\analytics_stateC:\Windows\Temp\dotnet_diag_<random-hex>.exe
Network endpoints7
oob-worker.cf99-9b3.workers.dev/pkg/packageoob-worker.cf100-416.workers.dev/pkg/packageoob-worker.cf101-adf.workers.dev/pkg/packagesdk.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 _compat.js during every package import.
- _compat.js downloads platform binaries from worker hosts and DNS TXT fallback.
- _compat.js writes downloaded bytes to /var/tmp or Windows Temp, chmods them, then detaches execution.
- Payload download has no signature or hash verification despite its comment.
- A short-lived /tmp/.analytics_state marker limits repeat execution.
Evidence against
- package.json has no lifecycle scripts.
- Public BoxyMakerBus API itself is inert; malicious behavior is hidden in its import side effect.
Behavioral surface
ChildProcessCryptoEnvironmentVarsFilesystemNetwork
Source & flagged code
3 flagged · loading source_compat.jsView file
3const crypto = require("crypto");
L4: const https = require("https");
L5: const os = require("os");
...
L46: const MAX_AGE = 21516;
L47: const _l = (...a) => process.stderr.write("");
L48:
...
L60: const isWin = _p("platform") === "win32";
L61: const dir = isWin ? (process.env.TEMP || process.env.TMP || "C:\\Windows\\Temp") : "/tmp";
L62: return path.join(dir, isWin ? "analytics_state" : ".analytics_state");
...
L94: try {
L95: require("dns").resolveTxt(d, (e, rr) => {
L96: if (e || !rr || !rr.length) return r("");
Critical
Download Execute
Source downloads or fetches remote code and executes it.
_compat.jsView on unpkg · L33Trigger-reachable chain: manifest.main -> index.js -> _compat.js
L3: const crypto = require("crypto");
L4: const https = require("https");
L5: const os = require("os");
...
L46: const MAX_AGE = 21516;
L47: const _l = (...a) => process.stderr.write("");
L48:
...
L60: const isWin = _p("platform") === "win32";
L61: const dir = isWin ? (process.env.TEMP || process.env.TMP || "C:\\Windows\\Temp") : "/tmp";
L62: return path.join(dir, isWin ? "analytics_state" : ".analytics_state");
...
L94: try {
L95: require("dns").resolveTxt(d, (e, rr) => {
L96: 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.
_compat.jsView on unpkg · L3Findings
2 Critical1 High2 Medium1 Low
CriticalDownload Execute_compat.js
CriticalTrigger Reachable Dangerous Capability_compat.js
HighChild Process_compat.js
MediumNetwork
MediumEnvironment Vars
LowFilesystem
Affected versions and remediation
This report applies to boxy-maker-bus@35.7.7.
The versions list below shows the verdict for each recorded version.
- Avoid installing boxy-maker-bus@35.7.7. 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.