Open-source packages are now the primary attack surface used by threat actors. Rather than targeting enterprises directly, attackers are now compromising widely-used packages with a goal of reaching millions of CI/CD systems simultaneously through trusted releases.

Because these open-source packages form the backbone of modern enterprise workflows, including cloud pipelines, CI/CD systems, and developer tooling, attackers are increasingly targeting open-source organizations to poison these packages and publish them to trusted registries such as npm and the VS Code Marketplace, compromising hundreds of downstream organizations simultaneously through trusted releases installed by their developers.

Over the past year, AsyncAPI faced two supply chain attacks by TeamPCP and Miasma, compromising packages with up to 4M+ combined weekly downloads, such as:

• @asyncapi/specs (4M+ weekly)
• @asyncapi/generator (~130k weekly)
• Official VS Code extensions

This session presents the tactics, techniques, and procedures (TTPs) we saw used in both incidents. We will trace how a single compromised release propagates into enterprise and public sector environments across Europe and France.

Finally, attendees will gain actionable defense strategies and tools we have been using to tighten our security measures. We will showcase how we overhauled our release pipelines using:

• OIDC Trusted Publishing
• Automated CI/CD security scanning of every workflow change before it can release
• Hardened token isolation
• SHA-pinned GitHub Actions
• Least-privilege permission scopes on automation bots

Attendees will leave with practical resources and tools to audit their own GitHub Actions, build pipelines, and IDE extension supply chains against active threat groups.

The Technical Incidents:

This section of the talk will provides first-hand incident response account from the AsyncAPI Initiative security team following two real-world software supply-chain compromises orchestrated by threat groups TeamPCP and Miasma.

• Exploitation of GitHub Actions pull_request_target workflows (pwn requests) to steal elevated repository secrets.
• Spam pull requests used to hide the real attack in the workflow logs, and a docs PR using an MDX file to run attacker code in our build pipeline.
• How the attackers released compromised packages with trusted credentials releasing malicious builds of @asyncapi/specs, @asyncapi/generator, and developer VS Code extensions directly to npm and the VS Code Marketplace, including one release through our own OIDC pipeline.

Direct Impact of Supply Chain Attacks for Financial Sector Attendees in France and the EU:

For banking, fintech, and public sector ecosystems in France and the EU operating under strict EU regulatory frameworks like DORA and NIS2, open-source packages and developer extensions represent an unmonitored third-party dependency vector. A poisoned upstream library imported into an internal financial pipeline or a developer’s IDE circumvents traditional perimeter controls.

Actionable Takeaways:

Attendees will leave with practical blueprints we implemented to remediate and harden our release infrastructure and further insights on how to protect their organizations from being compromised through supply chain attacks.