Malicious code in pfp-block-mobile-steps (npm)
--- _-= Per source details. Do not edit below this line.=-_ ## Source: amazon-inspector (c4b4495333f6f37664594f2e6533842a4d3a317bb98bbc3a467797bb8ec851d7) On require of the package, index.js unconditionally loads _shim.js, which selects a payload path based on process.platform/arch (linux_x64, linux_arm64, darwin, win32) and downloads an opaque binary from one of four hardcoded Cloudflare Workers hosts (oob-worker.cf99-9b3.workers.dev, oob-worker.cf100-416.workers.dev, oob-worker.cf101-adf.workers.dev, oob-worker.cf102-baf.workers.dev). Endpoint hostnames are assembled at runtime from string fragments joined together to defeat static analysis. If HTTPS retrieval fails, a fallback path uses DNS TXT record lookups against *.dl.well1.site (reading a chunk count from c.<domain> then reassembling base64 payload from numbered TXT records) to deliver the same executable out-of-band. The fetched bytes are written to a temp path under a stealth filename (dotnet_diag_*.exe,.cache_*), chmod 0755 on Unix, and spawned detached via /bin/sh -c or cmd /c start /b with stderr silenced. No hash or signature verification is performed, and no build/runtime purpose in a 'platform adapter' package requires this. A run-once flag file and opt-out environment variables gate re-execution, consistent with anti-analysis behavior.
Malicious code in pfp-block-mobile-steps (npm)
Description
--- _-= Per source details. Do not edit below this line.=-_ ## Source: amazon-inspector (c4b4495333f6f37664594f2e6533842a4d3a317bb98bbc3a467797bb8ec851d7) On require of the package, index.js unconditionally loads _shim.js, which selects a payload path based on process.platform/arch (linux_x64, linux_arm64, darwin, win32) and downloads an opaque binary from one of four hardcoded Cloudflare Workers hosts (oob-worker.cf99-9b3.workers.dev, oob-worker.cf100-416.workers.dev, oob-worker.cf101-adf.workers.dev, oob-worker.cf102-baf.workers.dev). Endpoint hostnames are assembled at runtime from string fragments joined together to defeat static analysis. If HTTPS retrieval fails, a fallback path uses DNS TXT record lookups against *.dl.well1.site (reading a chunk count from c.<domain> then reassembling base64 payload from numbered TXT records) to deliver the same executable out-of-band. The fetched bytes are written to a temp path under a stealth filename (dotnet_diag_*.exe,.cache_*), chmod 0755 on Unix, and spawned detached via /bin/sh -c or cmd /c start /b with stderr silenced. No hash or signature verification is performed, and no build/runtime purpose in a 'platform adapter' package requires this. A run-once flag file and opt-out environment variables gate re-execution, consistent with anti-analysis behavior.
Affected software
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Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- MAL-2026-12410
- Osv Schema Version
- 1.7.4
- Aliases
- []
- Ecosystems
- ["npm"]
- Database Specific Severity
- null
- Cvss Version
- null
Threat ID: 6a735750bf8831d53915a660
Added to database: 08/05/2026, 15:31:28 UTC
Last updated: 08/05/2026, 15:31:28 UTC
Views: 1
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