PYSEC-2026-3 Two telnyx versions published containing credential harvesting malware
Compromised telnyx library versions execute malware upon import, harvesting credentials and exfiltrating data to a remote server.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is PYSEC-2026-3?
PYSEC-2026-3 is a vulnerability in telnyx, published on 27 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
After an API token exposure from an exploited Trivy dependency,
two new releases of telnyx were uploaded to PyPI containing automatically activated malware,
harvesting sensitive credentials and files, and exfiltrating to a remote API.
Compromised versions execute code during importing the telnyx module through modifications in _client.py.
The code downloads the next stages from endpoints on the host 83.142.209[.]203, encoded in WAV files.
On Windows hosts, the malicious executable is placed in
%APPDATA%\Microsoft\Windows\Start Menu\Programs\Startup\msbuild.exe
for persistence and executed.
On other systems, the payload is a Python script.
After executing it, generated artifacts are exfiltrated to 83.142.209[.]203.
Version 4.87.1 contains a typo preventing the automated execution of the malicious code.
The code uses the encryption key observed in previous TeamPCP actions. The full compromise of exposed systems and all credentials reachable from them should be assumed. The credentials should be revoked/rotated, and the affected systems isolated and analyzed against malicious actions and modifications.
The two versions have been removed from PyPI, and the project has been reinstated.
Which versions are affected by PYSEC-2026-3?
1 open source package ship an affected version, including telnyx.
| Package | Affected | Fixed in |
|---|---|---|
telnyx PyPI | All versions | None |
How do I fix PYSEC-2026-3?
No fix has been published for PYSEC-2026-3 yet. Limit exposure of the affected software until one is available.
Is PYSEC-2026-3 being exploited?
There is no known exploitation of PYSEC-2026-3 in the wild and no public exploit code.