name: test
on:
push:
branches:
- "*"
jobs:
testBullFrog:
runs-on: ubuntu-22.04
steps:
- name: Use google dns
run: |
sudo resolvectl dns eth0 1.1.1.1
resolvectl status
- name: Set up bullfrog to block everything
uses: bullfrogsec/bullfrog@1472c28724ef13ea0adc54d0a42c2853d42786b1 # v0.8.2
with:
egress-policy: block
allowed-domains: |
*.github.com
- name: Test connectivity
run: |
echo testing udp allowed ..
dig api.github.com @1.1.1.1 || :
echo testing tcp allowed ..
dig api.github.com @1.1.1.1 +tcp || :
echo testing udp not allowed
dig api.google.com @1.1.1.1 || :
echo testing tcp not allowed
dig api.google.com @1.1.1.1 +tcp || :
Summary
While testing a potential bypass for https://github.com/bullfrogsec/bullfrog/security/advisories/GHSA-4gm5-gw8h-jmhw, I noticed that using tcp currently breaks blocking and allows DNS exfiltration.
PoC
Impact
sandbox bypass