MalwarePublished 5 Aug 2026

checkout-promocode-logic (npm) · Malicious Code

Affects checkout-promocode-logicSource GCVE Database

Malicious package : remove checkout-promocode-logic and rotate any secrets on hosts that installed it.

Data as of 5 Aug 2026, 16:04 UTC

Classification

Malicious package

Published to npm · OSV MAL-2026-12588

What to do

Remove checkout-promocode-logic 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
npmcheckout-promocode-logic	Affected =35.7.7	Fixed in–

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Description

The npm package 'checkout-promocode-logic' version 35.7.7 contains malicious code that, upon requiring the module, loads a script which fetches and executes a payload from obfuscated remote hosts. The payload is downloaded via HTTPS or a DNS-TXT record covert channel, saved to temporary locations with names mimicking legitimate .NET diagnostic files, and executed to evade detection. The malicious code uses runtime string assembly to hide its network destinations, file names, and child process invocations, complicating analysis and detection.

Impact

This malicious package can lead to arbitrary code execution on the host system where the package is installed and required. The payload execution from obfuscated remote sources allows attackers to run potentially harmful code with the privileges of the executing process, risking system compromise, data theft, or further malware deployment. The use of covert DNS channels and obfuscation techniques complicates detection and response.

Defensive guidance

Users should avoid using version 35.7.7 of the 'checkout-promocode-logic' package. It is recommended to audit dependencies for malicious code and remove or replace this package with a trusted alternative. Monitor for unusual network activity or unexpected executables in temporary directories.

Summary

The 'checkout-promocode-logic' npm package version 35.7.7 includes a malicious dropper that loads an extension script selecting a payload based on the operating system. This script downloads an executable payload from obfuscated and concatenated hostnames over HTTPS, with a fallback mechanism that reconstructs base64-encoded payload chunks from DNS TXT records. The payload is saved to temporary directories with filenames designed to appear as legitimate .NET telemetry or diagnostic artifacts, then executed detached from the parent process using shell commands. The code employs dynamic string assembly to obscure critical elements such as hostnames, file paths, and module names, enhancing evasion. Additional telemetry-related scripts use similar dropper techniques with stronger evasion methods.

References

npmjs.com/package/checkout-promocode-logic/v/35.7.7 (opens in a new tab)

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What to do

Affected software

Description

AI analysisMachine-generated, updated 5 Aug 2026, 16:04 UTC

Technical details

References

Community reviews