Coordinated Disclosure Timeline
- 2020-12-21: Issue reported to the Apache security team.
- 2021-01-25: Issue acknowledged.
- 2021-01-25: Apache/Camel-Website was added to the report.
- 2021-02-23: Asked for status update. Notified that Camel-Website repo is not fixed.
- 2021-03-22: Disclosure deadline reached.
- 2021-03-24: Asked for status update.
- 2021-04-29: The Camel team responded they just received the report 2021-04-28 6:58UTC
- 2021-04-29: Issue was fixed.
Summary
The pr.yaml GitHub workflow is vulnerable to unauthorized modification of the base repository or secrets exfiltration from a Pull Request.
Product
apache/camel-website GitHub repository
Tested Version
The latest changeset 52c23b5 to the date.
Details
Issue: Untrusted code is explicitly checked out and run on a Pull Request from a fork
Workflows triggered on pull_request_target have read/write tokens for the base repository and access to secrets. By explicitly checking out and running the build script from a fork the untrusted code is running in an environment that is able to push to the base repository and to access secrets. More details can be found in the article Keeping your GitHub Actions and workflows secure: Preventing pwn requests.
pr.yaml:
on: pull_request_target
...
- uses: actions/checkout@v2
with:
ref: ${{ github.event.pull_request.head.sha }}
persist-credentials: false
- name: Build
run: yarn build-all
Since the used package.json is controlled by the Pull Request creator it allows arbitrary code execution.
Impact
The vulnerability allows for unauthorized modification of the base repository and secrets exfiltration.
Credit
This issue was discovered and reported by GHSL team member @JarLob (Jaroslav Lobačevski).
Contact
You can contact the GHSL team at securitylab@github.com, please include a reference to GHSL-2020-364 in any communication regarding this issue.