Telnyx has malicious code in PyPI versions 4.87.1 and 4.87.2
Date: 2026-03
Affected: pip/telnyx
Attack vector: supply-chain
Category: vulnerability-disclosure
Severity: Critical
CWE: CWE-506

## 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 commit


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