Malicious code in checkout-desktop-promocode (npm)
--- _-= Per source details. Do not edit below this line.=-_ ## Source: amazon-inspector (19310e46ffcb5a99a81bab29f7260407b9fb6af5af72bdd8f3b9f7819cc6ffda) On require() of checkout-desktop-promocode, index.js loads _vendor.js which selects a per-platform endpoint, downloads a binary over HTTPS from obfuscated author-controlled hosts (sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru, net.dl.wel1.ru, and oob-worker.cf*-*.workers.dev), with a DNS-TXT chunked base64 covert-channel fallback. The fetched bytes are written to /tmp or %TEMP% under an innocuous filename (.cache_<rand> or dotnet_diag_<rand>.exe), chmod 0755'd, and spawned detached via /bin/sh -c or cmd.exe. C2 hostnames are assembled at runtime by Array.join on fragment arrays (e.g. ["oob-worker.cf99-9b3.w","orker","s.d","ev"].join("")) to evade static string scanners, and log calls are stubbed to a no-op writer. The package advertises itself as a promocode SDK but ships none of that functionality; the only effect of importing it is arbitrary attacker code execution on the installer's host.
Malicious code in checkout-desktop-promocode (npm)
Description
--- _-= Per source details. Do not edit below this line.=-_ ## Source: amazon-inspector (19310e46ffcb5a99a81bab29f7260407b9fb6af5af72bdd8f3b9f7819cc6ffda) On require() of checkout-desktop-promocode, index.js loads _vendor.js which selects a per-platform endpoint, downloads a binary over HTTPS from obfuscated author-controlled hosts (sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru, net.dl.wel1.ru, and oob-worker.cf*-*.workers.dev), with a DNS-TXT chunked base64 covert-channel fallback. The fetched bytes are written to /tmp or %TEMP% under an innocuous filename (.cache_<rand> or dotnet_diag_<rand>.exe), chmod 0755'd, and spawned detached via /bin/sh -c or cmd.exe. C2 hostnames are assembled at runtime by Array.join on fragment arrays (e.g. ["oob-worker.cf99-9b3.w","orker","s.d","ev"].join("")) to evade static string scanners, and log calls are stubbed to a no-op writer. The package advertises itself as a promocode SDK but ships none of that functionality; the only effect of importing it is arbitrary attacker code execution on the installer's host.
Affected software
Run on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- MAL-2026-12560
- Osv Schema Version
- 1.7.4
- Aliases
- []
- Ecosystems
- ["npm"]
- Database Specific Severity
- null
- Cvss Version
- null
Threat ID: 6a735732bf8831d53913d03d
Added to database: 08/05/2026, 15:30:58 UTC
Last updated: 08/05/2026, 15:30:58 UTC
Views: 1
Community Reviews
0 reviewsCrowdsource mitigation strategies, share intel context, and vote on the most helpful responses. Sign in to add your voice and help keep defenders ahead.
Want to contribute mitigation steps or threat intel context? Sign in or create an account to join the community discussion.
Actions
External Links
Need more coverage?
Upgrade to Pro Console for AI refresh and higher limits.
For incident response and remediation, OffSeq services can help resolve threats faster.
Latest Threats
Check if your credentials are on the dark web
Instant breach scanning across billions of leaked records. Free tier available.