Which versions of ac_calendar_ts are malicious?

The following npm versions of ac_calendar_ts are flagged malicious: 99.99.100. Treat any of these as compromised.

How do I remediate ac_calendar_ts if I installed it?

ac_calendar_ts 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 ac_calendar_ts — how do I know if it already compromised me?

If ac_calendar_ts was ever installed, its post-install/runtime payload may have already executed. O3's L7 egress monitoring and runtime eBPF sensors detect the credential exfiltration or command-and-control callback after install and block the malicious outbound channel, so you catch and contain the actual compromise — not just the presence of the package.

Is ac_calendar_ts part of a known attack campaign?

Yes — ac_calendar_ts is associated with the IN-MAL-2026-005009, GHSA-xgwp-29j2-jxj3 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 ac_calendar_ts across my projects, lockfiles, and CI pipelines?

Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for ac_calendar_ts (version 99.99.100). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging ac_calendar_ts across your stack and pipelines.

Malicious package

ac_calendar_tsnpm

ac_calendar_ts is a confirmed malicious npm package (MAL-2026-5434) that steals credentials and exfiltrates sensitive data (malicious version 99.99.100). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in ac_calendar_ts (npm)

MAL-2026-5434

Immediate action

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

npm uninstall ac_calendar_ts

What this malware does

On npm install, the package's canary.js postinstall script issues an HTTP GET to http://157.230.17.236/dc carrying the installer's os.hostname(), package name, version, a fixed nonce, and a phase identifier. The destination is a hardcoded bare IP over plain HTTP with no opt-in, no documented purpose, and no relationship to any declared package functionality. The package describes itself as a 'dependency-confusion canary,' which matches the pattern used to enumerate internal networks that resolved a public name — the installer's host identifier is exfiltrated to an external operator without consent. The version number (99.99.100) is also consistent with dependency-confusion targeting, in which an attacker publishes an artificially high version under a name expected to exist in a private registry.

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

1 flagged

99.99.100

Indicators of compromise (SHA-256)

d5b3fd92d67510aef112ac70c9af79a59b924eef29e20b1b127ea4c720182c63

e533a4e875c69b100794de172e9edb0158b0b3867cf3f59b4b367db8102c27a6

Detection & response playbook

Credential / info stealer

Find it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for ac_calendar_ts (version 99.99.100). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging ac_calendar_ts across your stack and pipelines.
If you installed it — respond
ac_calendar_ts 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 ac_calendar_ts was ever installed, its post-install/runtime payload may have already executed. O3's L7 egress monitoring and runtime eBPF sensors detect the credential exfiltration or command-and-control callback after install and block the malicious outbound channel, so you catch and contain the actual compromise — not just the presence of the package.
How O3 protects you
O3 blocks ac_calendar_ts before install through its supply-chain scanner, and if it has already run, detects and severs the exfiltration or C2 callback at runtime through L7 egress monitoring and eBPF.

Frequently asked questions

No. ac_calendar_ts on npm has been identified as a malicious package (version 99.99.100 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-005009GHSA-xgwp-29j2-jxj3

References

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks ac_calendar_ts-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

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