MalwarePublished 5 Aug 2026Updated 20 Aug 2026

devplatform-s3-client (npm) · Malicious Code

Affects devplatform-s3-clientSource GCVE Database

Malicious package : remove devplatform-s3-client and rotate any secrets on hosts that installed it.

Data as of 20 Aug 2026, 16:59 UTC

Classification

Malicious package

Published to npm · OSV MAL-2026-12747

What to do

Remove devplatform-s3-client 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
npmdevplatform-s3-client	Affected =35.9.5	Fixed in–

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Description

The devplatform-s3-client npm package version 35.9.5 contains malicious code that downloads and executes a platform-specific binary from Cloudflare Workers hostnames or via a covert DNS-TXT channel. The binary is saved under decoy filenames and executed to gain persistent control over the infected system. This behavior is unrelated to legitimate S3 client functionality. Systems with this package installed should be considered fully compromised, and all secrets and keys must be rotated immediately from a different device.

Impact

Any system with devplatform-s3-client version 35.9.5 installed or running is considered fully compromised. The attacker gains persistent remote code execution capabilities, potentially allowing full control over the system. All secrets and keys stored on the compromised system are at risk and must be rotated immediately from a secure, uncompromised device. Removing the package alone does not guarantee removal of all malicious artifacts or backdoors.

Defensive guidance

Immediate removal of the devplatform-s3-client package version 35.9.5 is required. All secrets and keys stored on the compromised system must be rotated from a separate, secure device. Due to the high likelihood of full system compromise, a full forensic investigation and system rebuild is recommended. Users should avoid using this package version and verify the integrity of any dependencies.

Summary

The devplatform-s3-client npm package version 35.9.5 includes malicious code in its main entry (_bridge.js) that constructs Cloudflare Workers hostnames from fragmented strings to download a platform-specific binary via HTTPS. This binary is saved to temporary directories under decoy names and executed with elevated permissions. If HTTPS downloads fail, the code uses a covert DNS-TXT channel to reconstruct and execute a base64-encoded binary. A persistence mechanism prevents repeated execution across imports. This malicious behavior is unrelated to the package's purported S3 client functionality and results in full system compromise.

References

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What to do

Affected software

Description

AI analysisMachine-generated, updated 20 Aug 2026, 16:59 UTC

Technical details

References

Community reviews