If this package is installed
Remove it, treat the machine (or CI runner) as compromised, and rotate every secret, token and key it could access — from a different, clean machine.
Details
Source: amazon-inspector (6f86ffde45262c5d45a24458a85116ab5ca80451ce3d3159f9d7cad6599ad145)
setup.py registers install, develop, and egg_info command hooks that run a routine which XOR-0x5A-decodes a list of attacker-controlled Cloudflare Workers hostnames (package-proxy.cf5oobworker.workers.dev and four sibling *.workers.dev hosts) and a URL path (/pkg/package), downloads opaque bytes over HTTPS, writes them to /var/tmp/.cache_<random>, chmods 0755, and spawns the binary detached via subprocess.Popen with start_new_session=True. If HTTPS fetch fails, it falls back to a DNS covert channel: raw DNS TXT queries against `*.lin.dl.wel1.ru` reassemble a base64 payload from serial subdomain lookups, which is then decoded and executed. All C2 hostnames, the URL path, and dynamic-import module names ('base64', 'b64decode', 'b32encode') are XOR-obfuscated byte literals whose only purpose is to hide the destinations from review. The hook is wired into egg_info as well as install/develop, so the payload fires during `pip install` and even during metadata-only operations. The package itself has no real functionality — src/haproxy_config_client/__init__.py contains only a __version__ string — and its name plus 'Internal service utilities' summary and 'TBank Engineering' author label are consistent with a dependency-confusion vehicle targeting an internal ops utility.
Source: kam193 (f70d07844bca4fadfcedb195f5768c8a95318af4d62a4bcec94556b99b72c4ad)
During installation the obfuscated code downloads a malicious executable from a remote location. Code is designed to survive different blocks: first, there is an attempt to download the executable from one of five Cloudflare Workers. If it's not successful, the code falls back to download using DNS: first, it gets a TXT record from c.lin.dl.wel1[.]ru. This record returns a number, which is then used to iterate over domains in the form <0...n>.lin.dl.wel1[.]r and reconstruct the encoded executable from their TXT records. The executable is finally saved under a partially random name, executed, and removed after execution. The Linux executable contacts a few domains, but there is no more detailed information about its behavior available.
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Category: MALICIOUS - The campaign has clearly malicious intent, like infostealers.
Campaign: 2026-07-haproxy-config-client
Reasons (based on the campaign):
- The package overrides the install command in setup.py to execute malicious code during installation.
- Downloads and executes a remote executable.
- obfuscation
- dependency-confusion
- other
- malware
- covering-tracks
- targetted-attack
- data-stored-in-dns
Indicators of compromise
Shown defanged and not clickable. Search any indicator to find other packages using it.
Domains
- package-proxy[.]cf5oobworker[.]workers[.]dev other packages →
- package-proxy[.]cf8oobworker[.]workers[.]dev other packages →
- package-proxy[.]cf12oobworker[.]workers[.]dev other packages →
- package-proxy[.]cf17-ddb[.]workers[.]dev other packages →
- package-proxy[.]cf25-6eb[.]workers[.]dev other packages →
- c[.]lin[.]dl[.]wel1[.]ru other packages →
URLs
- hxxps://package-proxy[.]cf5oobworker[.]workers[.]dev/pkg/package other packages →
- hxxps://package-proxy[.]cf8oobworker[.]workers[.]dev/pkg/package other packages →
- hxxps://package-proxy[.]cf12oobworker[.]workers[.]dev/pkg/package other packages →
- hxxps://package-proxy[.]cf17-ddb[.]workers[.]dev/pkg/package other packages →
- hxxps://package-proxy[.]cf25-6eb[.]workers[.]dev/pkg/package other packages →