Which versions of exodus-checkout-signer are malicious?

The following npm versions of exodus-checkout-signer are flagged malicious: 99.0.0-canary.1. Treat any of these as compromised.

How do I remediate exodus-checkout-signer if I installed it?

exodus-checkout-signer 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.

I already installed exodus-checkout-signer — how do I know if it already compromised me?

If exodus-checkout-signer 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.

Is exodus-checkout-signer part of a known attack campaign?

Yes — exodus-checkout-signer is associated with the IN-MAL-2026-005120, IN-MAL-2026-005119 campaign. Packages in the same campaign often share infrastructure and payloads, so check whether any related packages are also in your dependency tree.

How do I find exodus-checkout-signer across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for exodus-checkout-signer (version 99.0.0-canary.1).

Malicious package

exodus-checkout-signernpm

Advisory published Jun 9, 2026Updated Jun 9, 2026

exodus-checkout-signer is a confirmed malicious npm package (MAL-2026-5439) that steals credentials and exfiltrates sensitive data (malicious version 99.0.0-canary.1). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in exodus-checkout-signer (npm)

MAL-2026-5439

Immediate action

Remove the package, then rotate any secrets the build/runtime could reach.

npm uninstall exodus-checkout-signer

What this malware does

exodus-checkout-signer is the unscoped name of the scoped package @exodus/checkout-signer and self-describes (in README and package.json) as a dependency-confusion proof-of-concept targeting installers who follow Exodus's documented install command and drop the scope. The package's main entry throws on require so any caller fails loudly, but on npm install the postinstall script unconditionally runs node src/canary.js, which performs a DNS lookup and an HTTPS GET to 96e03fa6c292469a-172-245-86-254.serveousercontent.com — a Serveo SSH-tunneling endpoint with a raw IP (172.245.86.254) embedded in the subdomain — passing the package name and version as query parameters (/canary-install?pkg=...&ver=...). No installer secrets are exfiltrated, but every installation reveals the victim's source IP, timing, and corporate-network egress to an anonymous third-party tunnel operator that is not affiliated with the impersonated Exodus publisher. The combined name-confusion against a top-shelf wallet vendor's documented scope plus install-time beaconing to attacker-controllable infrastructure is a live supply-chain attack regardless of the author's stated 'research' intent.

Malicious versions

1 flagged

99.0.0-canary.1

Indicators of compromise (SHA-256)

7da50adb6560d5d1153657f16884e3acba9fd19865b0c1f6a90da176ae951f98

921c5ef246587db452bdb65aae12321f4de868e7882f9550f9b9e32300ae792c

Detection & response playbook

Credential / info stealer

Find it
Search your lockfiles and build artifacts for exodus-checkout-signer (version 99.0.0-canary.1).
If you installed it — respond
exodus-checkout-signer 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 exodus-checkout-signer 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

No. exodus-checkout-signer on npm has been identified as a malicious package (version 99.0.0-canary.1 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-005120IN-MAL-2026-005119

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks exodus-checkout-signer-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.

Malware detection Runtime egress monitoring

Explore

All malware advisories How O3 detects malware Vulnerability database