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

> Attackers compromised PyPI credentials to publish malicious Telnyx versions that steal cloud and local credentials upon import.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 30 Mar 2026

## What is GHSA-955r-262c-33jc?

GHSA-955r-262c-33jc is a vulnerability in telnyx, published on 30 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

## 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

## Which versions are affected by GHSA-955r-262c-33jc?

2 open source packages ship an affected version, including telnyx.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `telnyx` | PyPI | From 4.87.1 to 4.87.2 | None |
| `telnyx` | PyPI | From 4.87.1 to 4.87.2 | None |

## How do I fix GHSA-955r-262c-33jc?

No fix has been published for GHSA-955r-262c-33jc yet. Limit exposure of the affected software until one is available.

## Is GHSA-955r-262c-33jc being exploited?

There is no known exploitation of GHSA-955r-262c-33jc in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for GHSA-955r-262c-33jc and fix it if it is affected.

What it is: GHSA-955r-262c-33jc is a vulnerability in telnyx, published on 30 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of GHSA-955r-262c-33jc in the wild and no public exploit code.

Affected packages and fixed versions:
- telnyx (PyPI): affected from 4.87.1 up to 4.87.2; no fix listed
- telnyx (PyPI): affected from 4.87.1 up to 4.87.2; no fix listed

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/GHSA-955r-262c-33jc/ (Markdown: https://insights.sbomify.com/GHSA-955r-262c-33jc/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/GHSA-955r-262c-33jc

---
From sbomify Insights: https://insights.sbomify.com/GHSA-955r-262c-33jc/
Summaries are generated and may contain mistakes; the official description above is the record.