{"id":"MAL-2026-6325","summary":"Malicious code in web3-eth-util (npm)","details":"\n---\n_-= Per source details. Do not edit below this line.=-_\n\n## Source: amazon-inspector (f2e70ad91037bdc97e6b1ab8c95f5f2b5eecdb4524582d79dae5f240cbdbfc29)\nPackage name and metadata impersonate the legitimate @ethereumjs/util / ethereumjs-util packages: README is copied verbatim from the upstream ethereumjs project (and even instructs users to `npm install eth-util`), the contributor list and repository URL point at ethereumjs/ethereumjs-monorepo, but the package is published under a different name and ownership. The published dist/index.js (line ~57) contains `require(\"assertcore\")` and package.json declares `\"assertcore\": \"^3.1.7\"` as a runtime dependency. The human-authored src/index.ts has no such import, and the browser build at dist.browser/index.js also omits it — the extra require is injected only into the Node-targeted build that ships in the npm tarball, so reviewers reading the GitHub source see clean code while `npm install` + `require('web3-eth-util')` silently loads the third-party 'assertcore' package in the consumer's Node process with full privileges. 'assertcore' is not part of the legitimate @ethereumjs/util sources and resembles a typosquat of the standard 'assert' module. The combination — brand impersonation of a widely used Ethereum utility package, source/dist divergence hiding the injection from GitHub readers, and a require-time pull of an unrelated third-party package — is a dependency-chain dropper pattern that delivers attacker-controlled code to anyone who installs and imports this package.\n","modified":"2026-06-23T17:01:26.748649753Z","published":"2026-06-23T15:55:58Z","database_specific":{"malicious-packages-origins":[{"sha256":"f2e70ad91037bdc97e6b1ab8c95f5f2b5eecdb4524582d79dae5f240cbdbfc29","id":"IN-MAL-2026-007254","import_time":"2026-06-23T16:54:11.947277221Z","source":"amazon-inspector","modified_time":"2026-06-23T15:55:58Z","versions":["6.2.8"]}]},"references":[{"type":"PACKAGE","url":"https://www.npmjs.com/package/web3-eth-util/v/6.2.8"}],"affected":[{"package":{"name":"web3-eth-util","ecosystem":"npm","purl":"pkg:npm/web3-eth-util"},"versions":["6.2.8"],"database_specific":{"indicators":{"evidence_files":[{"sha256":"b58ae60ae0836b1569599e7f53790f6a70bb1ecd60e5b1232b5c76361c0afa22","tlsh":"8a51cc1b3658b8f583f860f81b2bd1c3f931593301b29a24866cd7f0dda698a85f4e1d","path":"dist/index.js"}],"package_integrity":[{"hashes":{"sha1":"e279959e4dd88d28e1ed1054565971ef83faef12","sha512_sri":"sha512-bk1Kn2+1lGeQkU/XKwnb3mixK6yzYz7leYHvjLsnuwQonW19Z15TjEpoH4RvzJPDjEZbWkK5WBXkppxGRhwqtQ=="},"filename":"web3-eth-util-6.2.8.tgz"}]},"cwes":[{"name":"Embedded Malicious Code","description":"The product contains code that appears to be malicious in nature.","cweId":"CWE-506"}],"source":"https://github.com/ossf/malicious-packages/blob/main/osv/malicious/npm/web3-eth-util/MAL-2026-6325.json"}}],"schema_version":"1.7.5","credits":[{"name":"Amazon Inspector","contact":["inspector-research@amazon.com"],"type":"FINDER"}]}