GHSA-955r-262c-33jc: Telnyx Telnyx Has Malicious Code Vulnerability
CRITICALGHSA-955r-262c-33jc is a CRITICAL telnyx has malicious code vulnerability (CWE-506: Embedded Malicious Code) affecting Telnyx libraries in the PyPI ecosystem. The issue involves telnyx has malicious code in pypi versions 4.87.1 and 4.87.2. Remediation is available in the latest vendor maintenance releases.
GHSA-955r-262c-33jc at a Glance
How to Fix GHSA-955r-262c-33jc
To remediate this vulnerability, upgrade all affected Telnyx dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.
pip install telnyx>=Latest secure release
Run the following command in your project directory to verify that all resolved dependencies use the patched release:
pip show telnyx
How to Check if You Are Affected
To determine whether your Python environment is affected by GHSA-955r-262c-33jc, inspect your installed packages using pip:
pip show telnyx
Analyze the terminal output to locate any version of Telnyx in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than the patched release), your application is affected.
Note: The pip show telnyx command checks currently installed packages in your active Python environment.
Technical Details
Vulnerability Mechanism & Technical Analysis
This vulnerability is classified under CWE-506: Embedded Malicious Code, where the product contains code that appears to be malicious in nature. In Telnyx, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.
Source Advisory Statement
GHSA-955r-262c-33jc Affected Telnyx Versions
1 component(s)| Product / Package | Ecosystem | Affected Versions | Fixed Version |
|---|---|---|---|
|
telnyx
|
PyPI |
≥ 4.87.1
≤ 4.87.2
|
|
References
Frequently Asked Questions
What is GHSA-955r-262c-33jc?
Which Telnyx versions are affected?
What version fixes GHSA-955r-262c-33jc?
Is telnyx affected?
What CWE is associated with GHSA-955r-262c-33jc?
How can I check PyPI dependencies for GHSA-955r-262c-33jc?
Machine-readable OSV JSON
OSV v1.5 Schema
{
"schema_version" : "1.4.0",
"id" : "GHSA-955r-262c-33jc",
"modified" : "2026-03-30T19:15:30Z",
"published" : "2026-03-30T19:15:30Z",
"aliases" : [ ],
"summary" : "Telnyx has malicious code in PyPI versions 4.87.1 and 4.87.2",
"details" : "## Summary\n\nOn March 27, 2026, a threat actor used compromised PyPI credentials to publish malicious versions 4.87.1 and 4.87.2 of the `telnyx` Python package directly to PyPI. These versions contain credential-stealing malware and were not published through the legitimate GitHub release pipeline.\n\n## Exposure Window\n\n| Version | Published (UTC) | Quarantined (UTC) | Exposure |\n|---------|-----------------|-------------------|----------|\n| 4.87.1 (broken) | 2026-03-27 03:51 | 2026-03-27 10:13 | 6h 22m |\n| 4.87.2 (functional) | 2026-03-27 04:07 | 2026-03-27 10:13 | 6h 6m |\n\n\n**Both versions were quarantined by PyPI at 2026-03-27 10:13 UTC.**\n\n**Note:** Version 4.87.1 contained a typo that prevented the malware from executing. Only 4.87.2 was fully functional.\n\n## Who Is Affected\n\nYou may be affected if:\n- You installed or upgraded the `telnyx` Python package between 03:51 UTC and 10:13 UTC on March 27, 2026\n- You ran `pip install telnyx` without pinning a version and received 4.87.1 or 4.87.2\n- A dependency in your project pulled in `telnyx` as a transitive, unpinned dependency\n\nYou are NOT affected if:\n- You pinned to version 4.87.0 or earlier\n- You installed before March 27, 2026 and did not upgrade\n- You built from GitHub source (malicious code was never committed to the repository)\n\n## Attack Details\n\n### Root Cause\n\nThe attacker obtained the PyPI API token and uploaded malicious packages directly to PyPI, bypassing the GitHub release pipeline entirely. No malicious commits exist in the GitHub repository.\n\n### Malicious Behavior\n\nThe malware is injected into `telnyx/_client.py` (74 additional lines) and executes on `import telnyx`:\n\n**Linux/macOS:**\n1. Spawns detached subprocess to survive parent exit\n2. Downloads payload hidden inside WAV audio file (steganography) from C2\n3. Harvests credentials: SSH keys, AWS/GCP/Azure creds, Kubernetes tokens, Docker configs, .env files, database credentials, crypto wallets\n4. If Kubernetes access found, deploys privileged pods to all nodes for lateral movement\n5. Encrypts with AES-256-CBC + RSA-4096, exfiltrates to C2\n\n**Windows:**\n1. Downloads binary hidden inside WAV file from C2\n2. Drops as `msbuild.exe` in Startup folder for persistence\n3. Executes with hidden window\n\n### Version Differences\n\n| Version | Status | Notes |\n|---------|--------|-------|\n| 4.87.1 | Broken | Typo: `Setup()` instead of `setup()` caused NameError |\n| 4.87.2 | Functional | Attacker uploaded 16 minutes later to fix their own casing error; full attack chain operational |\n\n## Verified Safe Version\n\n| Version | File | SHA-256 |\n|---------|------|--------|\n| **4.87.0** | `telnyx-4.87.0-py3-none-any.whl` | `5aeb8172c29ade224e6c2d166713f304596aa21e3dbfa5b6b2b028e6997f6bd2` |\n| **4.87.0** | `telnyx-4.87.0.tar.gz` | `3f093a85c313c2b779594f99fc07f453f1a7fd8785878d963688c531ff94d03a` |\n\n## Recommended Actions\n\n### 1. Check If You Are Affected\n\n```bash\n# Check installed version\npip show telnyx | grep Version\n\n# Check pip cache for telnyx versions\npip cache list telnyx 2>/dev/null\n\n# Check when telnyx was installed (modification time)\nls -la $(python -c \"import site; print(site.getsitepackages()[0])\")/telnyx* 2>/dev/null\n```\n\n### 2. Remove Compromised Versions\n\n```bash\npip uninstall telnyx\n```\n\n### 3. Rotate All Potentially Exposed Secrets\n\nIf there is any possibility that version 4.87.1 or 4.87.2 was installed in your environment, treat all accessible secrets as compromised:\n\n- SSH keys\n- AWS/GCP/Azure credentials\n- Kubernetes tokens and service accounts\n- Docker registry credentials\n- Database passwords\n- API keys in .env files\n- Telnyx API keys\n\n### 4. Check for Persistence (Linux/macOS)\n\n```bash\n# Check for malicious systemd service\nsystemctl --user status audiomon 2>/dev/null\nls -la ~/.config/audiomon/ 2>/dev/null\n\n# Check state file\nls -la /tmp/.initd_state 2>/dev/null\n```\n\n### 5. Check for Persistence (Windows)\n\n```powershell\n# Check Startup folder\nGet-ChildItem \"$env:APPDATA\\Microsoft\\Windows\\Start Menu\\Programs\\Startup\\msbuild.exe\"\n```\n\n### 6. Pin to Safe Version\n\n\n```bash\npip install telnyx==4.87.0\n```\n\nOr in requirements.txt:\n```\ntelnyx==4.87.0\n```\n\n## Indicators of Compromise\n\n### Malicious Package Hashes\n\n| File | SHA-256 |\n|------|--------|\n| `telnyx-4.87.1-py3-none-any.whl` | `7321caa303fe96ded0492c747d2f353c4f7d17185656fe292ab0a59e2bd0b8d9` |\n| `telnyx-4.87.2-py3-none-any.whl` | `cd08115806662469bbedec4b03f8427b97c8a4b3bc1442dc18b72b4e19395fe3` |\n\n### Network\n\n| IoC | Type |\n|-----|------|\n| `83.142.209.203` | C2 IP address |\n| `http://83.142.209.203:8080/ringtone.wav` | Payload endpoint (Linux/macOS) |\n| `http://83.142.209.203:8080/hangup.wav` | Payload endpoint (Windows) |\n| `http://83.142.209.203:8080/raw` | Persistence polling endpoint |\n\n### Filesystem\n\n| Path | Platform | Purpose |\n|------|----------|--------|\n| `~/.config/audiomon/audiomon.py` | Linux/macOS | Persistence implant |\n| `~/.config/systemd/user/audiomon.service` | Linux | Persistence service |\n| `/tmp/.initd_state` | Linux/macOS | State tracking |\n| `%APPDATA%\\Microsoft\\Windows\\Start Menu\\Programs\\Startup\\msbuild.exe` | Windows | Persistence binary |\n| `msbuild.exe.lock` | Windows | 12-hour cooldown lock |\n\n### Exfiltration\n\n- Archive name: `tpcp.tar.gz`\n- HTTP header: `X-Filename: tpcp.tar.gz`\n- Encryption: AES-256-CBC + RSA-4096 OAEP\n\n## Attribution\n\nThis attack is attributed to **TeamPCP** with high confidence based on:\n\n- Identical RSA-4096 public key as the LiteLLM compromise (March 24, 2026)\n- `tpcp.tar.gz` archive naming convention (TeamPCP signature)\n- Identical AES-256-CBC + RSA OAEP encryption scheme\n- Same credential harvesting targets and techniques\n\nRSA Key Hash:\n- PEM SHA-256: `4eceb569b4330565b93058465beab0e6d5ea09cfba8e7f29d7be1b5a2abd958a`\n\n## Resources\n\n- https://github.com/team-telnyx/telnyx-python/issues/235\n- https://www.endorlabs.com/learn/teampcp-strikes-again-telnyx-compromised-three-days-after-litellm\n- https://ramimac.me/teampcp",
"severity" : [ ],
"affected" : [ {
"package" : {
"ecosystem" : "PyPI",
"name" : "telnyx"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "4.87.1"
}, {
"last_affected" : "4.87.2"
} ]
} ]
} ],
"references" : [ {
"type" : "WEB",
"url" : "https://github.com/team-telnyx/telnyx-python/security/advisories/GHSA-955r-262c-33jc"
}, {
"type" : "WEB",
"url" : "https://github.com/team-telnyx/telnyx-python/issues/235"
}, {
"type" : "PACKAGE",
"url" : "https://github.com/team-telnyx/telnyx-python"
}, {
"type" : "WEB",
"url" : "https://ramimac.me/teampcp"
}, {
"type" : "WEB",
"url" : "https://www.endorlabs.com/learn/teampcp-strikes-again-telnyx-compromised-three-days-after-litellm"
} ],
"database_specific" : {
"cwe_ids" : [ "CWE-506" ],
"severity" : "CRITICAL",
"github_reviewed" : true,
"github_reviewed_at" : "2026-03-30T19:15:30Z",
"nvd_published_at" : null
}
}