actions / actions/actions-runner-controller

RUNNER_TOKEN is accessible from workflows running on the host

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#2,871 1 comment 5 reactions 0 assignees View on GitHub

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community enhancement needs triage
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Go
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Description

Currently RUNNER_TOKEN is protected from exfiltration using unset here after registering the agent but this doesn't prevent the secret from being leaked by accessing the parent process environ /proc/1/environ

jobs:
  printenv:
    name: printenv
    runs-on: [self-hosted]
    steps:
      - run: |
          grep --binary-files=text RUNNER_TOKEN /proc/1/environ | base64 -w 0

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Research direction

Start with runner/startup.sh around line 161 and reproduce the reported workflow that reads /proc/1/environ for RUNNER_TOKEN. Trace how the token remains available to the parent process, then verify that the completed change prevents the token from being exposed through that environment path.

Written by the indexing model from the issue text.

Assessment

Tech stack
shell
Domain
infrastructure, security
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
35/100

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