MAL-2026-10610: Malicious code in proxy-check-ii (PyPI)
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.
AI Analysis
Technical Summary
The proxy-check-ii package (version 0.1.0) on PyPI is a malicious package that installs a 7.7MB Go binary running an SSH/PTY server multiplexed over a yamux relay. The Python wrapper simply executes this binary without auditing or configuration, forwarding all arguments. The binary uses a hardcoded authorized SSH key and a relay network to establish a reverse-tunneled remote shell, enabling remote command execution on the victim's machine. The package metadata does not disclose this behavior and falsely claims to be a pure-Python wheel, misleading users. This constitutes a backdoor with clear malicious intent.
Potential Impact
Installation and execution of proxy-check-ii version 0.1.0 results in an unauthorized SSH daemon running on the victim machine, allowing remote attackers to execute commands remotely via a relay network. This backdoor bypasses direct port exposure and can facilitate persistent unauthorized access and control over the compromised system.
Mitigation Recommendations
No official patch or remediation is currently available. Users should avoid installing proxy-check-ii version 0.1.0 from PyPI. Remove any installations of this package immediately and audit systems for the presence of the qsshd binary and related processes. Monitor for unexpected SSH daemon activity and network connections to relay endpoints. Check the vendor or PyPI advisories for updates or removal notices.
MAL-2026-10610: Malicious code in proxy-check-ii (PyPI)
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.
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The proxy-check-ii package (version 0.1.0) on PyPI is a malicious package that installs a 7.7MB Go binary running an SSH/PTY server multiplexed over a yamux relay. The Python wrapper simply executes this binary without auditing or configuration, forwarding all arguments. The binary uses a hardcoded authorized SSH key and a relay network to establish a reverse-tunneled remote shell, enabling remote command execution on the victim's machine. The package metadata does not disclose this behavior and falsely claims to be a pure-Python wheel, misleading users. This constitutes a backdoor with clear malicious intent.
Potential Impact
Installation and execution of proxy-check-ii version 0.1.0 results in an unauthorized SSH daemon running on the victim machine, allowing remote attackers to execute commands remotely via a relay network. This backdoor bypasses direct port exposure and can facilitate persistent unauthorized access and control over the compromised system.
Mitigation Recommendations
No official patch or remediation is currently available. Users should avoid installing proxy-check-ii version 0.1.0 from PyPI. Remove any installations of this package immediately and audit systems for the presence of the qsshd binary and related processes. Monitor for unexpected SSH daemon activity and network connections to relay endpoints. Check the vendor or PyPI advisories for updates or removal notices.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- MAL-2026-10610
- Osv Schema Version
- 1.7.4
- Aliases
- []
- Ecosystems
- ["PyPI"]
- Database Specific Severity
- null
- Cvss Version
- null
Threat ID: 6a577ef368715ace43b415f0
Added to database: 07/15/2026, 12:37:07 UTC
Last enriched: 07/15/2026, 12:56:51 UTC
Last updated: 07/16/2026, 03:35:04 UTC
Views: 5
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