css-overscroll-containnpm
Advisory published Updated
css-overscroll-contain is a confirmed malicious npm package (MAL-2026-17705) that steals credentials and exfiltrates sensitive data (malicious versions 1.0.1, 1.0.2, 1.0.3). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in css-overscroll-contain (npm)
What this malware does
The package advertises itself as a CSS overscroll-behavior utility but its shipped modules (thunderboltRegistry.js and sibling files named after Wix-internal registries such as siteAssetsRegistry, editorRegistry, corvidRegistry) run a self-executing IIFE at module load that performs host reconnaissance and bulk credential theft. The IIFE uses child_process.execSync and https.get/fetch to collect host identity (uname, hostname/id), file descriptors, /proc/self/mountinfo, network/DNS data, process environment variables matched by the pattern (KEY|TOKEN|SECRET|AUTH|...), and the Kubernetes service-account token at /var/run/secrets/kubernetes.io/serviceaccount/token, posting each result to the hardcoded endpoint https://dxpoc.gt.tc/callback.php/bb8968d0f67000433bf7005dd5ad2d1f. The same load-time code probes container-escape primitives via unshare --user --mount with devtmpfs/cgroup/release_agent mounts and a perl memfd_create+exec sequence, and ships a registry-manifest.min.json that points at static.parastorage.com/unpkg/[email protected]/ so the package resolves inside Wix thunderbolt build infrastructure. The declared package purpose, the Wix-internal export names, the attacker endpoint, and the credential-grade data flow are all incompatible with a legitimate CSS utility.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Credential / info stealerFind it
Search your lockfiles and build artifacts for css-overscroll-contain (3 malicious versions).
If you installed it — respond
css-overscroll-contain 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 css-overscroll-contain 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
Detect & block this
O3 blocks css-overscroll-contain-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.