registry / Remote code execution / boxy-mmb-types
boxy-mmb-types
Lightweight boxy mmb types wrapper
This report shows the evidence for boxy-mmb-types@35.4.1, 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 import-triggered, unauthenticated download-and-execute chain is concrete remote code execution behavior and unrelated to the advertised type wrapper.
Static reason
High-risk behavior combination matched malicious policy.
Trigger
Runtime import/require of boxy-mmb-types.
Impact
Arbitrary attacker-controlled native code can execute under the importing process's user account.
Mechanism
remote payload download, disk drop, and detached execution
Attack narrative
A normal require of index.js silently requires _loader.js. The loader fetches a platform-specific binary from obfuscated Workers hosts, or reconstructs it from DNS TXT records, writes it to a temporary path, makes non-Windows payloads executable, and launches it via a detached shell or cmd.exe process. The payload is not authenticated despite a misleading integrity-check comment.
AI rationale
The import-triggered, unauthenticated download-and-execute chain is concrete remote code execution behavior and unrelated to the advertised type wrapper.
Evidence
package.jsonindex.js_loader.jslib/telemetry.js/tmp/.analytics_state/var/tmp/.cache_*C:\Windows\Temp\analytics_stateC:\Windows\Temp\dotnet_diag_*.exe
Network endpoints8
oob-worker.cf101-adf.workers.devoob-worker.cf99-9b3.workers.devoob-worker.cf103-070.workers.devoob-worker.cf100-416.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 _loader.js on every package import.
- _loader.js downloads platform payloads over HTTPS, with DNS TXT fallback.
- Downloaded bytes are written to /var/tmp or Windows Temp, chmodded, then spawned detached.
- Payload hosts are obfuscated by string concatenation; no checksum is verified.
- A temporary marker rate-limits repeated execution but does not prevent it.
Evidence against
- package.json contains no lifecycle scripts.
- The documented wrapper API itself is small and does not expose the loader.
Behavioral surface
ChildProcessCryptoEnvironmentVarsFilesystemNetwork
Source & flagged code
3 flagged · loading source_loader.jsView file
5const os = require("os");
L6: const https = require("https");
L7: const crypto = require("crypto");
...
L46: const MAX_AGE = 23057;
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");
...
L93: try {
L94: require("dns").resolveTxt(d, (e, rr) => {
L95: if (e || !rr || !rr.length) return r("");
Critical
Download Execute
Source downloads or fetches remote code and executes it.
_loader.jsView on unpkg · L55Trigger-reachable chain: manifest.main -> index.js -> _loader.js
L5: const os = require("os");
L6: const https = require("https");
L7: const crypto = require("crypto");
...
L46: const MAX_AGE = 23057;
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");
...
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.
_loader.jsView on unpkg · L5Findings
2 Critical1 High2 Medium1 Low
CriticalDownload Execute_loader.js
CriticalTrigger Reachable Dangerous Capability_loader.js
HighChild Process_loader.js
MediumNetwork
MediumEnvironment Vars
LowFilesystem
Affected versions and remediation
This report applies to boxy-mmb-types@35.4.1.
The versions list below shows the verdict for each recorded version.
- Avoid installing boxy-mmb-types@35.4.1. 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.