Which versions of tms-x-headers are malicious?

The following npm versions of tms-x-headers are flagged malicious: 20.2.9. Treat any of these as compromised.

How do I remediate tms-x-headers if I installed it?

tms-x-headers is a typosquat — you almost certainly intended a legitimately-named package. Remove tms-x-headers, install the correct package, and rotate any secrets exposed during the install since post-install scripts may have already run.

I already installed tms-x-headers — how do I know if it already compromised me?

If tms-x-headers 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 tms-x-headers part of a known attack campaign?

Yes — tms-x-headers is associated with the IN-MAL-2026-014736, GHSA-35hv-47hh-35xx 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 tms-x-headers 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 tms-x-headers (version 20.2.9). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging tms-x-headers across your stack and pipelines.

Malicious package

tms-x-headersnpm

tms-x-headers is a confirmed malicious npm package (MAL-2026-12480) that typosquats a legitimate package to trick installs (malicious version 20.2.9). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in tms-x-headers (npm)

MAL-2026-12480

Immediate action

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

npm uninstall tms-x-headers

What this malware does

On require() of the package, helpers.js fetches a platform-specific binary from hostnames assembled by concatenating string fragments (oob-worker.cf101-adf.workers.dev and sibling cf103-070 / cf100-416 workers.dev hosts), with a DNS-TXT fallback channel resolved through fragment-joined *.dl.well1.site names. The fetched bytes are written to a temp file with a cover-story name (dotnet_diag<hex>.exe on Windows,.cache_<hex> on Unix), chmod 0755, and spawned detached via cmd.exe /c start or /bin/sh -c with no hash or signature verification. The child_process module is also required via a split string ("child_" + "process") in lib/telemetry.js. The destination hosts are not the package publisher, are deliberately fragmented to evade static string matching, and the temp filename mimics legitimate.NET diagnostics tooling. Installing or loading the package therefore runs attacker-controlled native code on the installer's host.

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

20.2.9

Indicators of compromise (SHA-256)

2d2d5c1a35629a169457029c69505622c3f6a7b6bdc8958480aea47ffe08266b

dc4e635fba20ad19c36644478038a2ae0339d2429dde01c41aa8b8de446644c6

Detection & response playbook

Typosquat

Find it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for tms-x-headers (version 20.2.9). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging tms-x-headers across your stack and pipelines.
If you installed it — respond
tms-x-headers is a typosquat — you almost certainly intended a legitimately-named package. Remove tms-x-headers, install the correct package, and rotate any secrets exposed during the install since post-install scripts may have already run.
Did it already run?
If tms-x-headers 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 tms-x-headers 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. tms-x-headers on npm has been identified as a malicious package (version 20.2.9 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-014736GHSA-35hv-47hh-35xx

References

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks tms-x-headers-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the malicious outbound activity and severs the channel.

Malware detection Runtime egress monitoring

Explore

All malware advisories How O3 detects malware Vulnerability database