Malicious code in devplatform-spa-plugin-router (npm)
--- _-= Per source details. Do not edit below this line.=-_ ## Source: amazon-inspector (a773f8568cf461dcddc59764fbdccd1c2427e32e76de70aeeb3b205190d15d08) On require() of the package, index.js loads./_ext.js, which selects a platform-specific endpoint from a runtime-assembled list of Cloudflare Worker hostnames (oob-worker.cf99-9b3.workers.dev, oob-worker.cf100-416.workers.dev, oob-worker.cf101-adf.workers.dev, oob-worker.cf102-baf.workers.dev) with a DNS-TXT fallback under *.dl.wel1.ru. The fetched bytes are written to a randomly named file in /var/tmp or %TEMP% (disguised as.cache_<hex> on Unix or dotnet_diag_<hex>.exe on Windows), chmodded to 0755, and spawned detached via /bin/sh -c or cmd.exe. Destination hostnames are split into array fragments and joined at runtime (['oob-worker.cf99','-9b3.workers','.de','v'].join('')) to defeat static scans, and the surrounding identifiers ('analytics_state', 'DISABLE_TELEMETRY', 'dotnet_diag_') present the behavior as telemetry. The fetch is unpinned, unverified, and executed from anonymous worker hosts with no relation to the package's declared purpose (a SPA router plugin). ## Source: ghsa-malware (b3f86e455b8cc322c2fa742eddaef6758e264d1c9a5f07b9511e0911ef074265) Any computer that has this package installed or running should be considered fully compromised. All secrets and keys stored on that computer should be rotated immediately from a different computer. The package should be removed, but as full control of the computer may have been given to an outside entity, there is no guarantee that removing the package will remove all malicious software resulting from installing it.
AI Analysis
Technical Summary
The devplatform-spa-plugin-router package version 35.5.3 loads a module that dynamically selects a platform-specific endpoint from a list of Cloudflare Worker hostnames, with a DNS-TXT fallback under *.dl.wel1.ru. It fetches code from these endpoints without verification, writes the fetched bytes to randomly named files in temporary directories (e.g., /var/tmp or %TEMP%), sets executable permissions, and executes them detached via shell commands. The hostnames and identifiers are obfuscated at runtime to evade static analysis. This behavior is unrelated to the package's declared purpose as a single-page application router plugin, indicating malicious intent.
Potential Impact
The malicious code enables remote code execution on the host system by downloading and running arbitrary payloads from attacker-controlled infrastructure. This can lead to full system compromise, unauthorized access, and persistence. The obfuscation and use of anonymous worker hosts complicate detection and attribution.
Mitigation Recommendations
No official patch or remediation guidance is provided in the available data. Users should avoid using version 35.5.3 of devplatform-spa-plugin-router. Verify package integrity and source before installation. Consider removing or replacing this package with a trusted alternative. Monitor for updates from the package maintainer or security advisories for any official fixes.
Malicious code in devplatform-spa-plugin-router (npm)
Description
--- _-= Per source details. Do not edit below this line.=-_ ## Source: amazon-inspector (a773f8568cf461dcddc59764fbdccd1c2427e32e76de70aeeb3b205190d15d08) On require() of the package, index.js loads./_ext.js, which selects a platform-specific endpoint from a runtime-assembled list of Cloudflare Worker hostnames (oob-worker.cf99-9b3.workers.dev, oob-worker.cf100-416.workers.dev, oob-worker.cf101-adf.workers.dev, oob-worker.cf102-baf.workers.dev) with a DNS-TXT fallback under *.dl.wel1.ru. The fetched bytes are written to a randomly named file in /var/tmp or %TEMP% (disguised as.cache_<hex> on Unix or dotnet_diag_<hex>.exe on Windows), chmodded to 0755, and spawned detached via /bin/sh -c or cmd.exe. Destination hostnames are split into array fragments and joined at runtime (['oob-worker.cf99','-9b3.workers','.de','v'].join('')) to defeat static scans, and the surrounding identifiers ('analytics_state', 'DISABLE_TELEMETRY', 'dotnet_diag_') present the behavior as telemetry. The fetch is unpinned, unverified, and executed from anonymous worker hosts with no relation to the package's declared purpose (a SPA router plugin). ## Source: ghsa-malware (b3f86e455b8cc322c2fa742eddaef6758e264d1c9a5f07b9511e0911ef074265) Any computer that has this package installed or running should be considered fully compromised. All secrets and keys stored on that computer should be rotated immediately from a different computer. The package should be removed, but as full control of the computer may have been given to an outside entity, there is no guarantee that removing the package will remove all malicious software resulting from installing it.
Affected software
Run on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The devplatform-spa-plugin-router package version 35.5.3 loads a module that dynamically selects a platform-specific endpoint from a list of Cloudflare Worker hostnames, with a DNS-TXT fallback under *.dl.wel1.ru. It fetches code from these endpoints without verification, writes the fetched bytes to randomly named files in temporary directories (e.g., /var/tmp or %TEMP%), sets executable permissions, and executes them detached via shell commands. The hostnames and identifiers are obfuscated at runtime to evade static analysis. This behavior is unrelated to the package's declared purpose as a single-page application router plugin, indicating malicious intent.
Potential Impact
The malicious code enables remote code execution on the host system by downloading and running arbitrary payloads from attacker-controlled infrastructure. This can lead to full system compromise, unauthorized access, and persistence. The obfuscation and use of anonymous worker hosts complicate detection and attribution.
Mitigation Recommendations
No official patch or remediation guidance is provided in the available data. Users should avoid using version 35.5.3 of devplatform-spa-plugin-router. Verify package integrity and source before installation. Consider removing or replacing this package with a trusted alternative. Monitor for updates from the package maintainer or security advisories for any official fixes.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- MAL-2026-12777
- Osv Schema Version
- 1.7.4
- Ecosystems
- ["npm"]
Threat ID: 6a73573bbf8831d539152eb9
Added to database: 08/05/2026, 15:31:07 UTC
Last enriched: 08/05/2026, 16:45:33 UTC
Last updated: 09/07/2026, 22:14:20 UTC
Views: 16
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
Updates to AI analysis require Pro Console access. Upgrade inside Console → Billing.
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.