registry / postcss-theme-provider / 1.0.2

postcss-theme-provider@1.0.2

Production-ready PostCSS theme engine

AI Security Review

scanned 7d ago · by lpm-firewall-ai

Importing the core entrypoint executes a concealed remote payload loader. It derives C2 addresses from Ethereum data, downloads encoded code, evaluates it, and launches detached Node processes.

Static reason

No blocking static signals were detected.; previous stored version diff introduced dangerous source

Trigger

Importing postcss-theme-provider; plugin creation also reaches a duplicate loader.

Impact

Arbitrary attacker-controlled code execution in the consumer environment, with persistence-capable detached processes.

Mechanism

Blockchain-backed staged remote-code loader with eval and detached child process execution.

Attack narrative

The package hides an import-time loader after legitimate exports. It reads Ethereum blockchain data through public RPC services, extracts bytes to construct runtime HTTP hosts, fetches XOR-decoded payloads, evaluates one payload, and starts detached Node processes for both payloads. This is a staged remote-code-execution chain unrelated to a PostCSS theme plugin.

Rationale

Source inspection confirms concrete staged remote execution and detached process launch, not merely suspicious primitives. Absence of lifecycle hooks does not mitigate import-time execution.

Evidence

package.jsonpackages/core/package.jsonpackages/core/src/index.tspackages/core/src/plugin.ts

Network endpoints5

eth.blockscout.com/api1rpc.io/etheth.drpc.org

packages/core/src/index.ts and plugin.ts (compiled into dist/index.cjs referenced by main) contain a top-level async IIFE that executes on require of the package. The loader queries public Ethereum RPC endpoints (eth-mainnet.public.blastapi.io, eth.blockscout.com) for the latest transaction from a hardcoded attacker wallet (0xa322E5f3D311D3080e6f01210063e9aDC2490Ef1a), decodes two IPv4 addresses from the transaction's `to` field bytes, fetches XOR-encrypted JavaScript from http://<ip>:443/0x/cls and /0x/ls, decrypts it, calls eval on the result, and spawns a detached `node -e <payload>` child process via child_process.spawn with `unref()`. Module names, endpoints, method names, `spawn`, `eval`, and the wallet address are hidden using `\u00XX` unicode escapes (e.g. `require("\u0068\u0074\u0074\u0070")`, `require("\u0063\u0068\u0069\u006C\u0064\u005F\u0070\u0072\u006F\u0063\u0065\u0073\u0073")`) while legitimate PostCSS code in the same file uses normal string literals. The Ethereum-hosted dead-drop pattern (EtherHiding) lets the operator rotate the payload host by posting new transactions from the wallet; each import of the package fetches and executes whatever code the current C2 IP serves. ## Source: ghsa-malware (937f6ec3983bfe798ac6f21a95990720430b5a41f3629f9a408c48c765ab0dfa) 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.

postcss-theme-provider@1.0.2

AI Security Review

OSV Corroboration

Decision evidence

Source & flagged code

Source & flagged code

Findings

Source & flagged code