Malicious code in specials-obid-webpack (npm)
The npm package specials-obid-webpack contained malicious code that executed arbitrary binaries downloaded from attacker-controlled Cloudflare Workers hosts upon installation or require. The package used obfuscation techniques including string splitting, DNS-based covert channels, and disguised file paths to evade detection.
- Disclosed
- Last updated
- Blast radius
- Any system that installed or required the specials-obid-webpack package
- Ecosystems
- Attack vectors
- Affected entities
- specials-obid-webpackMalicious npm package containing remote code execution payload
The npm package specials-obid-webpack was found to contain malicious code that triggered remote code execution on any system where the package was installed or required. Upon package load, the _vendor.js module selected a platform-specific URL, downloaded a binary from attacker-controlled Cloudflare Workers hosts (oob-worker.cf99-9b3.workers.dev, oob-worker.cf100-416.workers.dev, oob-worker.cf101-adf.workers.dev, oob-worker.cf103-070.workers.dev), and executed it with elevated permissions.
The malware employed multiple obfuscation and evasion techniques to avoid detection. Destination hostnames were assembled at runtime using array .join("") operations, filenames were disguised to impersonate legitimate diagnostic tools (/tmp/.cache_ on Unix, %TEMP%\dotnet_diag_.exe on Windows), and code identifiers were split (e.g., "child_"+"process", "chmod"+"Sync") to evade static analysis.
A secondary dropper implementation was bundled in lib/telemetry.js using DNS-TXT covert channels to reassemble base64-encoded payloads from *.dl.well1.site. The package was identified by the OpenSSF malicious-packages project and credited to Amazon Inspector.
Indicators of compromise
- Packages
- specials-obid-webpack
- Domains
- oob-worker.cf99-9b3.workers.dev
- oob-worker.cf100-416.workers.dev
- oob-worker.cf101-adf.workers.dev
- oob-worker.cf103-070.workers.dev
- dl.well1.site
Remediation
- Immediately uninstall specials-obid-webpack from all systems
- Audit npm package.lock and yarn.lock files for any presence of specials-obid-webpack
- Review system logs and process execution history on any machine that installed or required this package for signs of unauthorized binary execution
- Block outbound connections to oob-worker.cf99-9b3.workers.dev, oob-worker.cf100-416.workers.dev, oob-worker.cf101-adf.workers.dev, oob-worker.cf103-070.workers.dev, and *.dl.well1.site at the network level
- Consider any system that installed this package as potentially compromised and perform forensic analysis
- Update npm security policies to flag and block this package
Sources
- GitHub Advisory GHSA-3g4w-f3vp-2cjp · GitHub Advisory Database
Cite this entry
"Malicious code in specials-obid-webpack (npm)." supplychainattack.org, Supply Chain Attack Incident Catalog. Disclosed August 5, 2026; last updated August 5, 2026. https://supplychainattack.org/incident/malicious-code-in-specials-obid-webpack-npm-euxa8e
Suggest a correction
Found an error or have a newer source? Corrections to factual errors take priority over new entries.
Related incidents
- containedcritical
Malware in svelte-dim-kit
The npm package svelte-dim-kit was found to contain malware, potentially giving attackers full control of affected systems. All systems with this package installed should be considered compromised and secrets/keys rotated immediately from a different computer.
npmCompromised package - containedcritical
Malicious code in @syncraft-labs/react (npm)
The npm package @syncraft-labs/react contained obfuscated malicious code in its ESM distribution that implements the EtherHiding pattern, fetching and executing arbitrary code from an Ethereum smart contract via RPC endpoints. The tampering occurred post-build in the dist/index.js artifact.
npmCompromised package - containedcritical
Malicious code in stillm4ddpocs-demo-sprocket (npm)
The npm package stillm4ddpocs-demo-sprocket version 999.9.12 contains malicious code that exfiltrates system and project metadata via multiple channels (HTTPS, HTTP, and DNS) to a hardcoded callback host. The package uses a high version number to exploit dependency-confusion attacks against organizations with internal packages of the same name.
npmCompromised packageDependency confusion - resolvedcritical
Malicious code in stillm4ddpocs-rtest-bravo (npm)
The npm package stillm4ddpocs-rtest-bravo contained malicious code in its preinstall script that automatically executed during installation, collecting system information and internal package metadata and exfiltrating it to a third-party Interactsh collector via HTTPS and DNS tunneling.
npmCompromised package