proxy-check-ii (PyPI) · Malicious Code
Affects proxy-check-iiSource GCVE Database
Malicious package : remove proxy-check-ii and rotate any secrets on hosts that installed it.
Data as of 15 Jul 2026, 12:56 UTC
Malicious package
Published to PyPI · OSV MAL-2026-10610
What to do
Remove proxy-check-ii from every project, lockfile and image that pulls it in. Treat any host that installed it as compromised: rotate the credentials, tokens and keys it could read, from a clean machine.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| PyPIproxy-check-ii | Affected
| Fixed in– |
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Description
The proxy-check-ii PyPI package version 0.1.0 contains malicious code that installs a prebuilt Go binary acting as a relayed SSH-like server. This backdoor allows remote command execution via a reverse-tunneled remote shell overlay without disclosing this behavior in the package metadata. The package misrepresents itself as a pure-Python wheel and does not provide transparency or configuration options for the embedded SSH daemon. The malicious functionality uses a hardcoded authorized key and a relay network to avoid direct exposure of ports on the victim machine.