#557: Security of everything at PyCon 2026

Summary of #557: Security of everything at PyCon 2026

by Michael Kennedy

1h 8m•August 2, 2026
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Overview of Security of Everything at PyCon 2026

This episode is a roundtable on the first-ever dedicated security track at PyCon US, featuring Seth Larson, Juanita Gomez, and Mike Fiedler. The conversation uses the track’s talks as a lens on the current state of Python security: supply-chain attacks, phishing, dependency cooldowns, zero trust, Rust in CPython, SBOMs, GitHub Actions risks, and why security is still very much an unsolved problem. The big theme: Python security is finally getting real attention, but it still needs more people, more tooling, and more funding.

Why the Security Track Mattered

  • PyCon US 2026 gave security its own day-long track, one of only two special tracks at the conference.
  • The room was packed, with some talks reaching standing-room-only levels.
  • The organizers saw the track as a signal that security is not a side topic—it applies to every Python project, maintainer, and user.
  • Juanita emphasized that security should be part of the default mindset for maintainers, even if they are not security experts.
  • Seth and Mike both stressed that dedicated funding and full-time security work make a real difference.

Key Themes From the Discussion

Security is Everyone’s Problem

  • Supply chain security affects every layer of the Python ecosystem, from core Python to packaging to third-party libraries.
  • Even if you write mostly application code, you depend on packages, tools, compilers, editors, operating systems, and infrastructure you do not control.
  • The speakers repeatedly returned to the idea that no one is fully isolated from the ecosystem.

Paid Security Work Helps, But Doesn’t Solve Everything

  • Mike described PyPI security as a full-time job with real impact, especially compared to volunteer-only efforts.
  • Seth noted the need to leave room for volunteer contribution rather than “snacking” on tasks that the community could take on.
  • The role of full-time security staff is to handle the high-impact, less volunteer-friendly work and to help others adopt better practices.

Open Source Security Needs Transparency

  • Because the work is at a nonprofit, the team can publish what they do, what works, and what they learn.
  • That makes it easier for maintainers and other projects to copy good practices instead of reinventing them.

Talk-by-Talk Highlights

Anatomy of a Phishing Campaign

  • Mike shared a real phishing attack against PyPI users and maintainers.
  • Attackers used lookalike domains and legitimate-looking emails to steal credentials.
  • Only a few accounts were affected, but one compromised package was especially dangerous because it was a dependency of a dependency in a major AI package chain.
  • The talk showed that:
    • TOTP-based 2FA helps against credential theft, but not against real-time phishing proxies.
    • WebAuthn/passkeys/YubiKeys provide stronger phishing resistance.
    • API tokens are powerful and should be treated carefully.

Dependency Cooldowns

  • The idea: delay pulling in newly published packages for a few days so scanners and humans have time to catch malicious releases.
  • Mike explained why this helps consumers who install latest versions automatically.
  • Juanita liked it as a secure default for less experienced developers.
  • Michael raised a real usability issue: cooldowns can conflict with vulnerability fixes, causing confusing dependency resolution problems.
  • The group agreed cooldowns are useful, but hard to make a universal default.

Zero Trust in 200 Milliseconds

  • This talk focused on identity-per-transaction patterns in regulated environments like FedRAMP.
  • It highlighted how much extra work is needed to make zero-trust systems practical.
  • The speakers appreciated that it brought a real-world, compliance-heavy perspective into a Python conference.

Rust in CPython

  • The discussion centered on proposals to rewrite some CPython components in Rust.
  • The speakers liked both the technical and community framing of the talk.
  • It was seen as a long-term effort, not a quick rewrite.
  • Starting with a module like zlib was discussed as a sensible first target because it processes untrusted data and is well understood.
  • A major point: the social challenge may be harder than the technical one.

SBOMs for Python Builds

  • The talk introduced SBOM tooling that can capture what actually happened during a build, not just what was declared.
  • The speakers liked the idea of making SBOMs more accurate and useful for real supply-chain tracking.
  • It was notable that the researchers were students who were trying to make their work directly usable by the community.

Post-Incident Runtime SBOM Generation

  • This talk explored deriving an SBOM from runtime or memory state after a process has run.
  • The value: see what was actually loaded and used, not just what should have been there.
  • The speakers liked the idea as a way to validate builds and potentially detect suspicious or unexpected code paths.
  • Seth noted that dynamic Python makes this harder, because code paths are not always straightforward to trace.

GitHub Actions Security in Python Packages

  • The talk highlighted how many Python projects have insecure or risky GitHub Actions setups.
  • A key danger: pull_request_target, which can execute with elevated privileges and is easy to misuse.
  • The recommended response is to run tools like Zizmor regularly and treat GitHub Actions as part of the attack surface.

Breaking Bad Packages

  • This talk focused on why traditional vulnerability tracking struggles with intentional malware.
  • CVEs work well for unintentional software flaws, but malware is a different category.
  • The speakers pointed out that supply-chain attacks often sit awkwardly between “vulnerability” and “malicious package,” and the ecosystem still lacks a perfect reporting system.

Main Takeaways

  • Python security is no longer a niche concern; it is an ecosystem-wide priority.
  • The packaging ecosystem has made real progress, but attackers only need one weak link.
  • Strong authentication, careful dependency management, and better build provenance are all important.
  • Tooling helps, but human process and community investment matter just as much.
  • Security is still not “solved,” which is exactly why the room was full.

Recommended Actions

For Python Users and Maintainers

  • Enable phishing-resistant 2FA where possible, especially WebAuthn/passkeys.
  • Review your dependency strategy:
    • Use version pins where appropriate.
    • Consider dependency cooldowns for less mature workflows.
  • Audit GitHub Actions with tools like Zizmor.
  • Use trusted publishing for package release workflows.
  • Check whether your build process can produce or consume SBOMs.

For Teams and Organizations

  • Invest in open source security work directly, either through funding or engineering time.
  • Support the projects and infrastructure your team depends on.
  • Treat package and CI security as part of normal software engineering, not as an afterthought.

Notable Closing Advice

  • Juanita: Use security tools more; even one improvement helps.
  • Mike: Convert at least one project to trusted publishing and delete the old token.
  • Seth: Support the open source ecosystems you rely on, because security work requires real resources.

Where to Find the Guests

  • Juanita Gomez: LinkedIn and her personal website
  • Mike Fiedler: miketheman.dev
  • Seth Larson: sethmlarson.dev, plus Mastodon, LinkedIn, and Signal