microsoft / microsoft/security-devops-azdevops

Which Defender CLI binary should be used in CI/CD pipelines — `aka.ms` or the DevOps CDN endpoint?

Open
#166 2 comments 1 reaction 0 assignees View on GitHub

Nobody has claimed this yet.

Dominant language
TypeScript
Stars
86
Forks
22
PR merge metrics
No merged PRs in 30d

Description

We're integrating Defender for Cloud image scanning into our Azure DevOps pipelines. Rather than using the MicrosoftDefenderCLI@2 task (which emits ##[error] for any findings regardless of the break setting), we're invoking the CLI binary directly so we can control exit code handling and surface findings as warnings.

We've discovered there are two different CLI binaries available:

Official (aka.ms) DevOps CDN
URL https://aka.ms/defender-cli_linux-x64 https://cli.dfd.security.azure.com/public/v2/latest/Defender_linux-x64
Size ~126 MB ~24 MB
Version v2.0.3334.114 (as of May 2026) Unknown — no --version output tested
Break flag --defender-break (critical only) --fail-on <severity> (configurable threshold)
Documented Yes — Install, Syntax, CI/CD No
Auth Token-based (client ID/secret) or connector Auto-detects SYSTEM_ACCESSTOKEN
SHA-256 79F4F1EDC1DD2F99193BFFC47464023A450CFEFA03F362D7716A5E51D357B0C1 CD31528812D19142DC58DEEA0475E2610F5CC4E4D036F78EAB2FF1243CC5BB3A
Observations
  1. The CDN binary appears purpose-built for CI/CD use. It's significantly smaller (24 MB vs 126 MB), supports a configurable severity threshold (--fail-on low|medium|high|critical), and auto-detects Azure DevOps pipeline authentication via SYSTEM_ACCESSTOKEN. The URL pattern (cli.dfd.security.azure.com/public/v2/latest/) suggests it's the same binary the MicrosoftDefenderCLI@2 task downloads internally.

  2. The aka.ms CLI is the documented standalone CLI. It's referenced in the official CI/CD integration guide for non-ADO platforms (GitHub Actions, Jenkins, etc.). Its --defender-break flag only exits non-zero for "critical issues" with no configurable threshold.

  3. The --help outputs are completely different. The CDN binary exposes flags like --fail-on, --baseline, --severity, --suppress, --quiet, and --timeout that don't exist in the aka.ms binary, and vice versa (e.g. --defender-debug, --defender-output only in aka.ms).

  4. Neither binary's scan image flags match the documented CLI reference exactly. The docs list --defender-break and --defender-output as global options, which align with the aka.ms binary but not the CDN one.

Questions
  1. Is the CDN endpoint (cli.dfd.security.azure.com) a supported, stable distribution channel? Can we rely on it in production pipelines, or is it an internal implementation detail of the ADO task that could change without notice?

  2. Are these intended to be two separate products, or are they converging? The feature sets (especially --fail-on vs --defender-break) suggest they may be independently developed.

  3. For Azure DevOps pipelines where we need to bypass the task wrapper (to avoid ##[error] on non-critical findings), which binary is recommended?

Contributor guide

No contributing guide indexed for this repository

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Start with the MicrosoftDefenderCLI@2 task and the linked Defender CLI install, syntax, and CI/CD documentation, then compare the documented aka.ms binary with the cli.dfd.security.azure.com endpoint. Done means establishing whether the CDN is supported and stable, whether the binaries are separate products, and which one Azure DevOps pipelines should use.

Written by the indexing model from the issue text.

Assessment

Tech stack
azure
Domain
ci-cd, devops
Issue type
Documentation
Difficulty
5/5
Estimated time
Over a week
Activity status
Quiet
Clarity
Needs clarification
Newbie friendliness
35/100

Get new issues in your inbox

A short digest of beginner-friendly GitHub issues.