GHSA-955r-262c-33jc Telnyx has malicious code in PyPI versions 4.87.1 and 4.87.2

• PyPI telnyx: >= 4.87.1, <= 4.87.2 (no fix yet)

Summary On 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. Exposure Window | Version | Published (UTC) | Quarantined (UTC) | Exposure | |---------|-----------------|-------------------|----------| | 4.87.1 (broken) | 2026-03-27 03:51 | 2026-03-27 10:13 | 6h 22m | | 4.87.2 (functional) | 2026-03-27 04:07 | 2026-03-27 10:13 | 6h 6m | Both versions were quarantined by PyPI at 2026-03-27 10:13 UTC. Note: Version 4.87.1 contained a typo that prevented the malware from executing. Only 4.87.2 was fully functional. Who Is Affected You may be affected if: • You installed or upgraded the `telnyx` Python package between 03:51 UTC and 10:13 UTC on March 27, 2026 • You ran `pip install telnyx` without pinning a version and received 4.87.1 or 4.87.2 • A dependency in your project pulled in `telnyx` as a transitive, unpinned dependency You are NOT affected if: • You pinned to version 4.87.0 or earlier • You installed before March 27, 2026 and did not upgrade • You built from GitHub source (malicious code was never committed to the repository) Attack Details Root Cause The 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. Malicious Behavior The malware is injected into `telnyx/_client.py` (74 additional lines) and executes on `import telnyx`: Linux/macOS: 1. Spawns detached subprocess to survive parent exit 2. Downloads payload hidden inside WAV audio file (steganography) from C2 3. Harvests credentials: SSH keys, AWS/GCP/Azure creds, Kubernetes tokens, Docker configs, .env files, database credentials, crypto wallets 4. If Kubernetes access found, deploys privileged pods to all nodes for lateral movement 5. Encrypts with AES-256-CBC + RSA-4096, exfiltrates to C2 Windows: 1. Downloads binary hidden inside WAV file from C2 2. Drops as `msbuild.exe` in Startup folder for persistence 3. Executes with hidden window Version Differences | Version | Status | Notes | |---------|--------|-------| | 4.87.1 | Broken | Typo: `Setup()` instead of `setup()` caused NameError | | 4.87.2 | Functional | Attacker uploaded 16 minutes later to fix their own casing error; full attack chain operational | Verified Safe Version | Version | File | SHA-256 | |---------|------|--------| | 4.87.0 | `telnyx-4.87.0-py3-none-any.whl` | `5aeb8172c29ade224e6c2d166713f304596aa21e3dbfa5b6b2b028e6997f6bd2` | | 4.87.0 | `telnyx-4.87.0.tar.gz` | `3f093a85c313c2b779594f99fc07f453f1a7fd8785878d963688c531ff94d03a` | Recommended Actions 1. Check If You Are Affected ```bash Check installed version pip show telnyx | grep Version Check pip cache for telnyx versions pip cache list telnyx 2>/dev/null Check when telnyx was installed (modification time) ls -la $(python -c "import site; print(site.getsitepackages()[0])")/telnyx* 2>/dev/null ``` 2. Remove Compromised Versions ```bash pip uninstall telnyx ``` 3. Rotate All Potentially Exposed Secrets If there is any possibility that version 4.87.1 or 4.87.2 was installed in your environment, treat all accessible secrets as compromised: • SSH keys • AWS/GCP/Azure credentials • Kubernetes tokens and service accounts • Docker registry credentials • Database passwords • API keys in .env files • Telnyx API keys 4. Check for Persistence (Linux/macOS) ```bash Check for malicious systemd service systemctl --user status audiomon 2>/dev/null ls -la ~/.config/audiomon/ 2>/dev/null Check state file ls -la /tmp/.initd_state 2>/dev/null ``` 5. Check for Persistence (Windows) ```powershell Check Startup folder Get-ChildItem "$env:APPDATA\Microsoft\Windows\Start Menu\Programs\Startup\msbuild.exe" ``` 6. Pin to Safe Version ```bash pip install telnyx==4.87.0 ``` Or in requirements.txt: ``` telnyx==4.87.0 ``` Indicators of Compromise Malicious Package Hashes | File | SHA-256 | |------|--------| | `telnyx-4.87.1-py3-none-any.whl` | `7321caa303fe96ded0492c747d2f353c4f7d17185656fe292ab0a59e2bd0b8d9` | | `telnyx-4.87.2-py3-none-any.whl` | `cd08115806662469bbedec4b03f8427b97c8a4b3bc1442dc18b72b4e19395fe3` | Network | IoC | Type | |-----|------| | `83.142.209.203` | C2 IP address | | `http://83.142.209.203:8080/ringtone.wav` | Payload endpoint (Linux/macOS) | | `http://83.142.209.203:8080/hangup.wav` | Payload endpoint (Windows) | | `http://83.142.209.203:8080/raw` | Persistence polling endpoint | Filesystem | Path | Platform | Purpose | |------|----------|--------| | `~/.config/audiomon/audiomon.py` | Linux/macOS | Persistence implant | | `~/.config/systemd/user/audiomon.service` | Linux | Persistence service | | `/tmp/.initd_state` | Linux/macOS | State tracking | | `%APPDATA%\Microsoft\Windows\Start Menu\Programs\Startup\msbuild.exe` | Windows | Persistence binary | | `msbuild.exe.lock` | Windows | 12-hour cooldown lock | Exfiltration • Archive name: `tpcp.tar.gz` • HTTP header: `X-Filename: tpcp.tar.gz` • Encryption: AES-256-CBC + RSA-4096 OAEP Attribution This attack is attributed to TeamPCP with high confidence based on: • Identical RSA-4096 public key as the LiteLLM compromise (March 24, 2026) • `tpcp.tar.gz` archive naming convention (TeamPCP signature) • Identical AES-256-CBC + RSA OAEP encryption scheme • Same credential harvesting targets and techniques RSA Key Hash: • PEM SHA-256: `4eceb569b4330565b93058465beab0e6d5ea09cfba8e7f29d7be1b5a2abd958a` Resources • https://github.com/team-telnyx/telnyx-python/issues/235 • https://www.endorlabs.com/learn/teampcp-strikes-again-telnyx-compromised-three-days-after-litellm • https://ramimac.me/teampcp