AWS CodeBuild Misconfiguration Exposed GitHub Repos to Potential Supply Chain Attacks
16.01.2026
5181
A misconfigured AWS CodeBuild webhook allowed bypass of actor ID checks, risking takeover of four AWS GitHub repositories before fixes in Sep 2025.
AWS CodeBuild Misconfiguration Exposed GitHub Repos to Potential Supply Chain Attacks
Yikes, AWS just dodged a major supply chain bullet. A misconfigured CodeBuild webhook could've let attackers hijack FOUR of their GitHub repos. The flaw? Bypassing actor ID checks like they weren't even there.
Here's the tea: AWS CodeBuild's webhook validation was basically sleeping on the job. Attackers could've spoofed GitHub webhooks to trigger builds from ANY repo they wanted. No auth? No problem. This wasn't just theoretical—it risked full repo takeover.
The scary part? This wasn't some edge case. The misconfiguration meant CodeBuild would just trust ANY incoming webhook claiming to be from GitHub. No verification of who actually sent it. Classic case of 'trust but don't verify' gone wrong.
AWS fixed this in September 2025 (props for the quick patch), but imagine if bad actors found it first. They could've injected malicious code into AWS's own repos, creating a supply chain nightmare for EVERYONE using those services.
- • Misconfigured AWS CodeBuild webhook
- • Bypassed actor ID checks completely
- • Risked takeover of 4 AWS GitHub repositories
- • Could've enabled supply chain attacks
- • Fixed by AWS in September 2025
Lesson for all you DevOps folks: ALWAYS validate your webhooks. AWS got lucky this time, but next time might not be so forgiving. Your CI/CD pipeline is only as strong as its weakest link—and apparently, that link was wide open.
#AWS CodeBuild#GitHub vulnerabilities#supply chain attacks#unauthenticated access#misconfigurations
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