Malicious code in devplatform-s3-client (npm)
--- _-= Per source details. Do not edit below this line.=-_ ## Source: amazon-inspector (618b016d2ee8f333f47ee78c4ffe29b703a08ab7fca524ee072944394fb1301c) On require of the package's main entry, _bridge.js assembles Cloudflare Workers hostnames from string fragments via Array.join (e.g. 'oob-worker.cf102-baf.workers.dev', 'cf101-adf.workers.dev', 'cf99-9b3.workers.dev'), downloads a platform-specific binary via https.get, writes it to /var/tmp or %TEMP% under a decoy name (.cache_<rnd> on Unix, dotnet_diag_<rnd>.exe on Windows), sets it executable with chmod 0755, and spawns it detached via /bin/sh -c or cmd.exe /c start /b. If HTTPS fetches fail, _bridge.js falls back to a DNS-TXT covert channel: it resolves TXT records at c.<domain> and numbered subdomains under an obfuscated 'sdk.dl.wel1.ru' family to reassemble a base64-encoded binary, then writes and executes it. A persistence-stamp file gates re-execution across imports. The hostnames are split into fragments to evade static grep, decoy filenames masquerade as OS diagnostic caches, and none of this behavior is part of an S3 client.
Malicious code in devplatform-s3-client (npm)
Description
--- _-= Per source details. Do not edit below this line.=-_ ## Source: amazon-inspector (618b016d2ee8f333f47ee78c4ffe29b703a08ab7fca524ee072944394fb1301c) On require of the package's main entry, _bridge.js assembles Cloudflare Workers hostnames from string fragments via Array.join (e.g. 'oob-worker.cf102-baf.workers.dev', 'cf101-adf.workers.dev', 'cf99-9b3.workers.dev'), downloads a platform-specific binary via https.get, writes it to /var/tmp or %TEMP% under a decoy name (.cache_<rnd> on Unix, dotnet_diag_<rnd>.exe on Windows), sets it executable with chmod 0755, and spawns it detached via /bin/sh -c or cmd.exe /c start /b. If HTTPS fetches fail, _bridge.js falls back to a DNS-TXT covert channel: it resolves TXT records at c.<domain> and numbered subdomains under an obfuscated 'sdk.dl.wel1.ru' family to reassemble a base64-encoded binary, then writes and executes it. A persistence-stamp file gates re-execution across imports. The hostnames are split into fragments to evade static grep, decoy filenames masquerade as OS diagnostic caches, and none of this behavior is part of an S3 client.
Affected software
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Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- MAL-2026-12747
- Osv Schema Version
- 1.7.4
- Aliases
- []
- Ecosystems
- ["npm"]
- Database Specific Severity
- null
- Cvss Version
- null
Threat ID: 6a735739bf8831d53914f79b
Added to database: 08/05/2026, 15:31:05 UTC
Last updated: 08/05/2026, 15:31:05 UTC
Views: 1
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