MalwarePublished 5 Aug 2026

bigops-watchdog-worker (npm) · Malicious Code

Affects bigops-watchdog-workerSource GCVE Database

Malicious package : remove bigops-watchdog-worker and rotate any secrets on hosts that installed it.

Data as of 6 Aug 2026, 19:33 UTC

Classification

Malicious package

Published to npm · OSV MAL-2026-12856

What to do

Remove bigops-watchdog-worker from every project, lockfile and image that pulls it in. Treat any host that installed it as compromised: rotate the credentials, tokens and keys it could read, from a clean machine.

Affected software

Product	Affected	Fixed in
npmbigops-watchdog-worker	Affected =35.7.4	Fixed in–

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Description

The npm package bigops-watchdog-worker version 35.7.4 contains malicious code that downloads and executes a remote binary payload on affected systems. This payload is fetched from non-publisher-controlled domains and executed with elevated permissions, masquerading as a Microsoft diagnostic tool. The malware includes anti-analysis features to evade detection and can fully compromise the host system. Removal of the package does not guarantee eradication of the malware, and all secrets on the system should be considered compromised and rotated immediately.

Impact

Any system with this package installed or running is considered fully compromised. The attacker may have full control over the host, including access to all secrets and keys stored on the system. Because the malware downloads and executes a remote binary, it can perform arbitrary malicious actions. Simply removing the package does not guarantee removal of all malicious components or persistence mechanisms.

Defensive guidance

Immediate removal of the bigops-watchdog-worker package version 35.7.4 is recommended. All secrets, keys, and credentials stored on the affected system should be rotated from a separate, trusted environment. Due to the high likelihood of full system compromise, consider rebuilding the affected system from a known good state. Monitor for any signs of persistence or additional malicious activity.

Summary

The bigops-watchdog-worker npm package (version 35.7.4) includes malicious functionality where its index.js loads a runtime script that reconstructs remote hostnames from split string fragments. It selects a URL based on the host platform and architecture, downloads an opaque binary over HTTPS, writes it to a temporary location, sets executable permissions, and spawns it detached. If HTTPS download fails, it falls back to retrieving a base64 payload via DNS TXT records. The binary masquerades as a Microsoft diagnostic executable. Anti-analysis techniques include caching execution state to suppress repeated runs and honoring environment variables to appear benign. The remote hosts involved are not controlled or affiliated with the package publisher. This behavior results in full system compromise, with potential exposure of all stored secrets and keys.

References

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What to do

Affected software

Description

AI analysisMachine-generated, updated 6 Aug 2026, 19:33 UTC

Technical details

References

Community reviews