# MAL-2026-12541: Malicious code in checkout-accounts-holder (npm)


- **Type:** Malicious package
- **Package:** `checkout-accounts-holder` (npm)
- **Published:** 5 Aug 2026

## What is MAL-2026-12541?

MAL-2026-12541 is a malicious package in checkout-accounts-holder, published on 5 Aug 2026. 

### Official description

On `require('checkout-accounts-holder')`, index.js loads _platform.js which immediately downloads a platform-specific binary over HTTPS from hostnames assembled at runtime via `.join("")` over split string fragments (resolving to `oob-worker.cf100-416.workers.dev` with a DNS TXT fallback under `sdk.dl.wel1.ru`), writes the opaque payload to /tmp or %TEMP% under cover names such as `.cache_<rand>` and `dotnet_diag_<rand>.exe`, chmods it 0o755, and spawns it detached via `/bin/sh -c "<path> &"` or `cmd.exe /c start`. The module presents itself as `analytics_state`/telemetry. A second dropper of the same shape ships in lib/telemetry.js (base64-chunked payload, `fs["chmod"+"Sync"]`, `require("child_"+"process")`, `spawn("/bin/sh", ["-c", filePath + " &"])`), currently unreferenced but present in the published tarball. Destination hostnames are string-split to evade plain-text scanners, and the run-write-chmod-spawn chain executes attacker-controlled bytes with the installer's privileges.

## What should I do about MAL-2026-12541?

Remove the package from your dependencies and lockfiles, then rotate any secrets on machines where it was installed.

## Fix prompt for AI coding agents

```text
MAL-2026-12541 is a malicious package: checkout-accounts-holder (npm). Every version was published to cause harm.

Task:
1. Search this repository's dependency manifests and lockfiles for the package, including transitive dependencies.
2. If it is present, remove it, regenerate the lockfile with the project's package manager, and replace whatever it was used for.
3. List any CI runners, developer machines or containers that installed it, so their secrets can be rotated.
4. If the package is not used anywhere, say so and change nothing.

Reference: https://insights.sbomify.com/MAL-2026-12541/ (Markdown: https://insights.sbomify.com/MAL-2026-12541/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/MAL-2026-12541

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From sbomify Insights: https://insights.sbomify.com/MAL-2026-12541/
Summaries are generated and may contain mistakes; the official description above is the record.