MAL-2026-4523 Malicious code in claude-channel-imessage (npm)
- Package
- claude-channel-imessage
- Registry
- npm
What is MAL-2026-4523?
MAL-2026-4523 is a malicious package in claude-channel-imessage, published on 25 May 2026.
Official description
On npm install, postinstall.js executes whoami and id, reads os.hostname(), os.platform(), process.cwd(), and the CI, GITHUB_REPOSITORY, and NODE_ENV environment variables, then transmits them as querystring parameters over HTTPS to qys3a81jtkh128ob7n3nvg4fz651tvhk.oastify.com (a Burp Collaborator subdomain controlled by a third party). The script additionally performs a DNS lookup of <whoami>.qys3a81jtkh128ob7n3nvg4fz651tvhk.oastify.com, embedding the installer's local username into a DNS query to leak it over a covert channel that succeeds even when outbound HTTP is filtered. The package self-describes as a 'Security research canary' but the dual-channel beacon (HTTPS + DNS) to an attacker-controlled collaborator host fires unconditionally on every install, leaking internal CI identity, repository names, and host identifiers from any environment that installs the package.
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.
What should I do about MAL-2026-4523?
Remove the package from your dependencies and lockfiles, then rotate any secrets on machines where it was installed.
Sources
Also known as GHSA-6v88-cxrw-54h7.