← NIST SP 800-204D
5.1.3
Integrity of evidence generation during software updates
The evidence that a release is genuine (signatures, provenance, update metadata) must be produced by a process an attacker cannot tamper with, and must be checked by consumers.
Summary in ghtier's words. Read NIST 800-204D's own text
Incidents (5)
Last 12 months (2): ChainDrop: a hijacked maintainer account publishes through trusted publishing, TeamPCP tag force-overwrite campaign
2026
- ChainDrop: a hijacked maintainer account publishes through trusted publishingOrganization August 2026
- TeamPCP tag force-overwrite campaignOrganization March 2026
2025
- Shai-Hulud self-propagating worm (1.0 & 2.0)Organization September 2025
- tj-actions/changed-files supply-chain compromise (CVE-2025-30066)Application March 2025
2024
- Ultralytics build cache poisoningOrganization December 2024
Attack path techniques used
- Push directly, without review (Submit malicious code)
- Delete branches and workflow runs (Delete code or cover tracks)
- Push a release tag to an unreviewed commit (Point a release tag at a bad commit)
- Repoint existing tags on a published Action (Point a release tag at a bad commit)
- Add a workflow that dumps secrets (Steal CI secrets and tokens)
- Run PR code in a privileged workflow (Steal CI secrets and tokens)
- Read secrets from the runner (Steal CI secrets and tokens)
- Poison a shared Actions cache (Poison the build or published package)
- Publish a malicious version with a stolen token (Poison the build or published package)
- Flip private repos to public (Read or expose private code)
- Register the attacker's machine as a runner (Keep access)
Checklist items
The fixes for those techniques.
- Branch protection on default/release branches: required reviews + required status checks
- Rulesets applied: push restriction, tag protection, sensitive file-path protection
- Enable audit logging and export it to a SIEM for retention and detection
- Third-party Actions pinned to a full commit SHA instead of a mutable tag or branch
- CODEOWNERS in place, required on sensitive paths
- Inventory every Actions secret and its visibility/scope; the results are usually surprising
- Cloud credentials migrated from static keys to OIDC federation, scoped to repo + branch
- Audit every use of pull_request_target and remove or restructure risky ones
- Set the default GITHUB_TOKEN permission to read-only at the org level
- Require approval for first-time/external contributor workflow runs on forks
- Restrict which Actions can run to GitHub-verified creators or an internal allow-list
- Adopt artifact attestations for build provenance on published binaries/images
- Publish packages with trusted publishing (OIDC) instead of long-lived registry tokens
- Put production secrets in environments with required reviewers
- Write and rehearse a credential-rotation runbook before you need it
- Restrict public repo creation, visibility changes, repo deletion, private forks and outside collaborator invites to owners
- Limit the number of organization owners to the minimum needed
- Disallow self-hosted runners on public repositories
Permissions involved
The GitHub permissions those incidents abused.