What's the best way to prevent accidental github leaks? I once accidentally leaked an API key (albeit for a relatively unimportant service, and I realized soon afterwards).
It's possible to monitor them while pushing code, and to have a monitoring system deployed to track them.
I was thinking of open-sourcing our GitHubSniper tool, it basically has API regex from nearly a thousand SaaS and PaaS services and frequently posted sensitive strings, can be deployed via docker ;)
The only thing that stops me from releasing it is I have consistently earned more in bounties than the incentives of actually releasing it publicly. But will eventually release it :)
Nevermind...I found the docs. :-)
* Don't blindly add everything to git.
* Check staged files before commit.
* Store secrets separately, outside of your git folder (e.g. use another folder, service or environment variables).
* If it must be in your git folder, then make use of .gitignore and store keys, etc separately from code in files with a unique file name pattern.
First off, I'm pushing the principle that secrets should only be issued, created, stored and distributed by the secret management system, vault in our case. If you never see a secret, and only instruct the automation how to handle it, it is much harder to leak the secret. Ideally, in production, no human should ever need to see or access the secret.
Second, you should have good rotation procedures. Something will eventually leak, or someone will leave on bad terms and you need to be able to handle that. This can be simple - an HA infra service can just reload the core credentials from vault and be done, or somewhat harder, e.g. if customers need and use those passwords.
And finally, you should have entropy scanners like trufflehog or github scanners as linked in other tools - both in you precommit hooks (so you cannot commit the secret) as well as in your CI & repository host, so someone who disabled the security scanner "because it was annoying" still gets caught.
And I guess finally, whiskey for that friday evening someone still manages to leak something important. Some terminations at work have not been fun.
- a good, tested key rotation practice will reduce the impact of any accidental exposures. It'll also help tremendously when staff changes, and you can do things like "rotate all keys every quarter"
- separate API keys for different services and environments means that even if your staging network-layer key is exposed, it can't affect your staging database (= data), nor your production database (= critical data).
- I've used "search for AWS secrets" as a pre-commit and also CI hook with great luck. I've even accidentally added a secret myself :) but with the checks the error was immediately found. No problems!
Otherwise, secrets as environment variables, do not write them down in files, and change them regularly.
If you change them too often then it's a maintenance problem. You might even take an outage because you have mismatched credentials (i.e. application or database had the database credentials updated but the other one didn't)
Changing them regularly IS necessary. So if you're going to do it you should use a credential service like Hashicorp Vault.
If you instinctively want to write
shiny_api_key = 'SOME.KEY.BOSS.EMAILED.ME'
Force yourself to instead take the extra few minutes to do
# my-cloud-vendor key-store create shiny_api_key SOME.KEY.BOSS.EMAILED.ME
and then write
shiny_api_key = key_store_access('shiny_api_key')
This way, when six hours later you check that code in, to GitHub, and go home for the weekend, you won't get a call from the boss ruining your Sunday lie-in, "WTF Did you upload our $5000 shiny API key to GitHub? You are fired".
This habit also allows for correct separation as an organisation grows, when you're big enough you want it to be possible for somebody to write code against test systems with test API keys, and that same code to work as written in production, even though production API keys are not accessible to the coders. Using key stores to mediate makes this much more likely to actually work.
Build in the secret retriving function from day one. Have it grab from an environment variable and it will be 100% seamless from development to production. Add more complexity/security if and when you need it.
This can later be leveraged to allow for zero-downtime credential rotations for running services, which allows for seamless use of ephemeral credentials, which is what we should all be moving towards.
The right answer here (as stated in sibling comments) is to install a mechanism into the build. A push that accidentally commits credentials should break the build. How it goes about doing that is up to you, but the specific way I've done that in the past is a git hook [1] specifically the pre-commit hook. It looks like there's a reasonably well-updated package by Yelp to help do this kind of thing [2].
[1] https://git-scm.com/book/en/v2/Customizing-Git-Git-Hooks [2] https://github.com/Yelp/detect-secrets
These types of hook are brittle. If you already knew you were supposed to do it the way I wrote, you get a hook failure, you say "D'oh" and you do it properly. But if you aren't trained to do anything in particular, this type of hook is a behavioural branch. Maybe it's 0845, your mentor just arrived, the perfect time to ask what the diagnostic means. "You need to use a dedicated key store, let me show you" she says and you just learned an important thing.
But maybe it's 1845, you're the last one in the office. You promised to raise a PR for tomorrow, but the hook fails. You try some things, and eventually discover that it hides well enough if split into four strings. You commit, click to raise the PR and go home.
And the person who reads that PR will see immediately tomorrow it's unacceptable because it has an obfuscated API key, but alas if it's a real working key that's too late.
You raise a great point which is that these kinds of mechanisms are only as strong as the cultures that support them. If the team doesn't wholeheartedly digest and commit to the new mechanism, it will at best achieve only surface level improvements.
Getting your team's culture to that point is a step zero of sorts -- completely necessary precondition and you can't do much without it. And that can end up with people paying lip service to the letter but not spirit of the mechanism.
I add this hook which checks for passwords, high-entropy strings, etc. and has tools for managing false positives: https://github.com/Yelp/detect-secrets
Here is their comparison of pre-commit hooks and other tools. It's current and comprehensive. https://github.com/duo-labs/secret-bridge/blob/master/TOOLS....
Not perfect but gets you maybe 80-90% of the way.
If you are super paranoid you air-gap everything.
Don't use GitHub. Guaranteed to have 100% efficacy.