fix(release): narrow S3 egress wildcards to Apple notary bucket - #138
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The *.s3.amazonaws.com and *.s3.us-west-2.amazonaws.com wildcards matched any S3 bucket, leaving a general-purpose outbound write path open in the one job that holds the signing P12 and tap token. The harden-runner log from the successful v0.5.3 run (32801379092) shows the only S3 host actually contacted is notary-submissions-prod.s3.us-west-2.amazonaws.com (quill's upload to Apple's notary service); nothing ever matched the global wildcard. Replace both with that specific hostname.
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What
Replaces the two wildcard S3 entries in the goreleaser job's harden-runner allowlist with the one specific hostname a release actually contacts:
*.s3.amazonaws.com:443,*.s3.us-west-2.amazonaws.com:443notary-submissions-prod.s3.us-west-2.amazonaws.com:443Why
The wildcards resolve to any S3 bucket, including one an attacker controls. This job holds the macOS signing P12, the notary key, and the Homebrew tap token — the workflow's own comment calls it the prime exfiltration target. Every other allowlist entry is a specific host; these two were the only general-purpose outbound write path left open, so a compromised dependency could
PUTto an arbitrary bucket and the egress policy would allow it.Both wildcards were added preemptively in #130 rather than from observed traffic. The harden-runner log from the successful v0.5.3 run (32801379092) shows the only S3 host contacted is
notary-submissions-prod.s3.us-west-2.amazonaws.com— quill's upload to Apple's notary submission bucket. Nothing ever matched the*.s3.amazonaws.comglobal wildcard. The bucket-specific host closes the exfil path: the hostname pins the bucket, and that bucket is Apple's.Caveat
This job only fires on
v*tags, so CI on this PR cannot exercise the change. If Apple ever moves the notary bucket (or quill switches to the global/accelerate S3 endpoint), the next release fails loudly on a blocked connection and the harden-runner report names the endpoint to re-add — the same discipline already written into the workflow comment. Worth cutting the next release soon after merging to confirm.