Ensure Source Code Management (SCM) email notifications are restricted to verified domains

MediumLevel 2Automatedgithub

Description

Restrict the Source Code Management (SCM) organization's email notifications to approved domains only. Restricting Source Code Management email notifications to verified domains only prevents data leaks, as personal emails and custom domains are more prone to account takeover via DNS hijacking or password breach. GraphQL notificationDeliveryRestrictionEnabledSetting must be ENABLED (GitHub Enterprise Cloud; enforced at enterprise level counts when it shows as enabled on the organization). Uses the GitHub REST/GraphQL API through gh api (read-only). The repository comes from GH_REPO or the current git checkout (gh's {owner}/{repo} resolution, GH_HOST for GitHub Enterprise Server); the organization comes from GH_ORG (default: the repository owner). Fails when gh is missing or unauthenticated (gh auth login or GH_TOKEN); organization settings and branch protection need an owner/admin token.

How it is checked

Audit method: Shell command

shell

command -v gh >/dev/null 2>&1 || exit 1
gh auth status >/dev/null 2>&1 || exit 1
O=${GH_ORG:-$(gh api 'repos/{owner}/{repo}' --jq .owner.login 2>/dev/null)}
[ -n "$O" ] || exit 1
v=$(gh api graphql -f query='query($o: String!) { organization(login: $o) { notificationDeliveryRestrictionEnabledSetting } }' -f o="$O" --jq '.data.organization.notificationDeliveryRestrictionEnabledSetting == "ENABLED"' 2>/dev/null) || exit 1
[ "$v" = true ] && echo compliant

Expected output: compliant

How it is fixed

Fix method: Guidance or infrastructure patch

Organization (or enterprise) Settings > Verified and approved domains: enable Restrict email notifications to only approved or verified domains.

Properties

Operating systems: Any
Tags: githubsource-code
Reference: CIS GitHub Benchmark v1.2.0 - 1.3.10 Ensure Source Code Management (SCM) email notifications are restricted to verified domains

Check this host

Run this on a machine you are allowed to audit. The scan is read-only.

shell

tmaegis scan --target github --level 2