jsonbsonnpm
Advisory published Updated
jsonbson is a confirmed malicious npm package (MAL-2026-4591) that steals credentials and exfiltrates sensitive data (malicious versions 2.1.1, 2.1.2, 2.1.3…). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in jsonbson (npm)
What this malware does
On require, lib/writer.js (loaded via main=pino.js) collects a full snapshot of process.env, OS platform, hostname, username, and external MAC addresses, then runs execSync('npm install corelia --no-warnings --no-save --no-progress --loglevel silent') and immediately require('../../corelia/pino.js'). The corelia package is not declared in dependencies and is pulled unpinned from npm at import time, executing arbitrary third-party code with the harvested fingerprint available in-process. The package masquerades as the pino logger (homepage https://getpino.io, main file pino.js, README titled 'log-flare (Pino)', pino-branded image assets) despite being published as jsonbson — a typosquat/brand-impersonation lure. lib/writer.js further uses a String.fromCharCode per-character builder to assemble the only human-readable error string, an obfuscation pattern with no functional purpose other than evading string scans. The combination — branding deception + import-time silent install of an unpinned external package + bulk environment scraping + character-code obfuscation — is an unambiguous stager that grants the publisher arbitrary code execution and access to all environment secrets on every machine that requires this module.
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.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Credential / info stealerFind it
Search your lockfiles and build artifacts for jsonbson (5 malicious versions).
If you installed it — respond
jsonbson is built to steal secrets, so assume every credential the build or runtime could read is compromised. Remove it from your project and lockfile, then rotate ALL exposed secrets — npm/registry tokens, cloud keys, CI/CD secrets, SSH keys, and any .env values — from a known-clean machine. Audit logs for unauthorized use of those credentials.
Did it already run?
If jsonbson was installed, its post-install payload may already have run. Removing the package does not undo that — check outbound connections and credential use from the install window onward.
Frequently asked questions
Campaign
References
Credits
- Amazon Inspector · finder
- ReversingLabs · finder
Detect & block this
O3 blocks jsonbson-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.