MAL-2026-12655 Malicious code in cobrowsing-k8s-module (npm)
Malicious package
Published
MAL-2026-12655 is a malicious package: cobrowsing-k8s-module (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-2026-12655/ (Markdown: https://insights.sbomify.com/MAL-2026-12655/index.md)
- Package
- cobrowsing-k8s-module
- Registry
- npm
What is MAL-2026-12655?
MAL-2026-12655 is a malicious package in cobrowsing-k8s-module, published on 5 Aug 2026.
Official description
On require of the package's main entry, bridge.js selects a platform-specific endpoint, reconstructs remote hostnames at runtime via array.join("") string-split obfuscation (oob-worker.cf100-416.workers.dev, oob-worker.cf102-baf.workers.dev, oob-worker.cf103-070.workers.dev, and sdk/ext/pkg/net.dl.wel1.ru), fetches an opaque binary over HTTPS, writes it to a hidden temp path with cover-story filenames (dotnet_diag.exe,.cache_,.analytics_state), chmods 0755, and spawns it detached via child_process spawn("/bin/sh") or spawn("cmd"). If HTTP fetch fails, the code falls back to a DNS-TXT covert channel that reads a chunk count from c.<domain> and reassembles base64-encoded binary chunks across numbered TXT records under *.dl.wel1.ru to bypass HTTP egress filters. No hash or signature verification is performed. The behavior is disguised as analytics/telemetry.
What should I do about MAL-2026-12655?
Remove the package from your dependencies and lockfiles, then rotate any secrets on machines where it was installed.