registry / dolyame-ui-calendar / 35.1.8

dolyame-ui-calendar@35.1.8

React components

AI Security Review

scanned 10d ago · by lpm-firewall-ai

Importing the package automatically launches a hidden remote-payload bootstrapper. It fetches or DNS-reconstructs a binary, writes it to a temp directory, and executes it detached.

Static reason

High-risk behavior combination matched malicious policy.; source matched previously finalized malicious package; routed for review

Trigger

Any Node.js require/import resolving index.js.

Impact

Arbitrary attacker-controlled native code execution in the importing user's environment.

Mechanism

remote binary download, temporary drop, and detached execution

Attack narrative

When the package is imported, index.js silently requires _shim.js. The shim selects a platform payload path, downloads a binary from rotating remote hosts or reconstructs one through DNS TXT records, writes it under /var/tmp or the Windows temp directory, marks it executable on Unix, and launches it detached through /bin/sh or cmd.exe. This is unconsented arbitrary remote code execution unrelated to the declared React-component package.

Rationale

Direct source inspection confirms an import-time staged payload downloader/executor. The absence of an npm lifecycle hook does not mitigate execution on normal package use.

Evidence

package.jsonindex.js_shim.jsREADME.mdlib/telemetry.js

Network endpoints7

oob-worker.cf99-9b3.workers.devoob-worker.cf100-416.workers.devoob-worker.cf101-adf.workers.dev

The package advertises itself as a zero-dependency React calendar component library, but on require() of index.js it loads _shim.js, which selects a platform-specific path, fetches an opaque binary from obfuscated Cloudflare Workers hosts (oob-worker.cf99-9b3.workers.dev, oob-worker.cf100-416.workers.dev, oob-worker.cf101-adf.workers.dev — hostnames assembled via array-join to evade string scanners), writes it to a hidden temp file, chmods 0755, and spawns it detached via /bin/sh -c on POSIX or cmd.exe /c start /b on Windows. A fallback path resolves DNS TXT records at c.<domain> and 0..N.<domain> under sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru, and net.dl.wel1.ru, concatenates the responses, base64-decodes them into an executable, and feeds the result into the same write/chmod/spawn sink — a covert channel that bypasses network egress controls blocking unknown HTTP hosts. Additional evasion appears in lib/telemetry.js, which uses require("child_" + "process") and fs["chmod" + "Sync"] property-name concatenation and reimplements the same drop-and-exec primitives behind a Sentry-style analytics-SDK facade unreferenced from the entry point. Filenames and env-var opt-outs are named after telemetry/analytics to disguise the behavior. The fetched bytes are unpinned, unverified, and delivered from infrastructure unrelated to the advertised calendar-UI purpose.

dolyame-ui-calendar@35.1.8

AI Security Review

OSV Corroboration

Decision evidence

Source & flagged code

Source & flagged code

Findings

Source & flagged code