Public secrets exposure leads to supply chain attack on GitHub CodeQL

297 points by cyberbender 3 months ago | 61 comments
  • Sytten 3 months ago
    An again this would not be so bad an impact if github finally pushed their immutable actions [1]. I sound like a broken record since I keep repeating that this would solve like 70%+ of the scope of attacks on gha today. You would think that the weekly disaster they have would finally make them launch it.

    [1] https://github.com/features/preview/immutable-actions

    • thund 3 months ago
      They probably have good reasons if it's still in preview, that could be serious bugs, security gaps, potential breaking changes that would cause more harm than good if rushed, etc
      • 1oooqooq 3 months ago
        the only reason any company does or don't anything: not required for sales.

        in 2019 i saw a fortune500 tech company put in place their own vulnerability scanner internal application which included this feature for our enterprise github repos. the tool was built and deployed to an old Linux docker image that was never updated to not be the target of the attack they were preventing... they never vetted to random version they started with either. i guess one can still use zip bomb or even the xz backdoor for extra irony points when attacking that system.

        anyway, the people signing github checks also get promoted by pretending to implement that feature internally.

        • intelVISA 3 months ago
          Too much stakeholder alignment?
          • tanepiper 3 months ago
            More like last year they laid off a whole bunch of people. We've been waiting for several open tickets on GitHub to be picked up, some were but seem to be abandoned and others just ignored.
      • nyrikki 3 months ago
        No mention why this temp token had rights to do things like create a new deployments and generate artifact attestations?

        For their fix, they disabled debug logs...but didn't answer if they changed the temp tokens permissions to something more appropriate for a code analysis engine.

        • declan_roberts 3 months ago
          I think we all know this old story. The engineer building it was getting permission denied so they gave it all the permissions and never came back and right-sized.
          • setr 3 months ago
            Does any RBAC system actually tell you the missing permissions required to access the object in question? It’s like they’re designed to create this behavior
            • Normal_gaussian 3 months ago
              Yes. Most auth systems do to the developer - GCP & AWS IAM give particularly detailed errors; nearly every feature/permission system I have implemented did. However, it wouldn't be unusual for the full error to be wrapped or swallowed by some lazy error handling. Its a bit of a PITA but well worth it to translate to a safe and informative user facing error.

              as a nit; RBAC is applied to an object based permissions system rather than being one. Simply, RBAC is a simplification of permission management in any underlying auth system.

              • Uvix 3 months ago
                Azure’s RBAC system usually tells you this, at least when accessing the Azure management APIs. (Other APIs using RBAC, like the Azure Storage or Key Vailt ones, usually aren’t so accommodating. At least by their nature there’s usually only a handful of possible permissions to choose from.)
                • levkk 3 months ago
                  Not usually, that's considered an potential attack vector I believe. You're looking to minimize information leakage.
                  • UltraSane 3 months ago
                    AWS has a neat feature to analyze cloudtrail logs to determine needed permissions.
                  • azemetre 3 months ago
                    What's the over/under that said engineer could solve two medium leetcodes in under and hour?
                  • Pathogen-David 3 months ago
                    If the GitHub Actions temporary token does not have workflow-defined permissions scope, it defaults either to a permissive or restricted default scope based on the repository's setting. This setting can also be configured at the organization level to restrict all repos owned by the org.

                    Historically the only choice was permissive by default, so this is unfortunately the setting used by older organizations and repos.

                    When a new repo is created, the default is inherited from the parent organization, so this insecure default tends to stick around if nobody bothers to change it. (There is no user-wide setting, so new repos owned by a user will use the restricted default. I believe newly created orgs use the better default.)

                    [0]: https://docs.github.com/en/actions/security-for-github-actio...

                    • beaugunderson 3 months ago
                      Temporary action tokens have full write by default; you have to explicitly opt for a read-only version.

                          > Read and write permissions
                          > Workflows have read and write permissions in the repository for all scopes.
                      
                      If you read this line of the documentation (https://docs.github.com/en/actions/security-for-github-actio...) you might think otherwise:

                          > If the default permissions for the GITHUB_TOKEN are restrictive, you may have to elevate the permissions to allow some actions and commands to run successfully.
                      
                      But I can confirm that in our GitHub organization "Read and write permissions" was the default, and thus that line of documentation makes no sense.
                      • stogot 3 months ago
                        The 2023 Microsoft hack (that CISA completely called them out for poor security) also was similar to this. Their blog post that tried to explain what happened left so many unanswered questions
                        • Elucalidavah 3 months ago
                          > For their fix, they disabled debug logs

                          For their quick fix, hopefully not for their final fix.

                          • arccy 3 months ago
                            just goes to show how lax microsoft is about their security. nobody should trust them.
                          • ashishb 3 months ago
                            I am getting more and more convinced that CI and CD should be completely separate environments. Compromise of CI should not lead to token leaks related to CD.
                            • mdaniel 3 months ago
                              This area is near and dear to my heart, and I would offer that the solution isn't to decouple CD over into its own special little thing but rather to make the CD "multi factor" in that it must be "sub":"repo:octo-org/octo-repo:environment:prod"[1] and feel free to sprinkle in any other [fun claims][] you'd like to harden that system

                              1: https://docs.github.com/en/actions/security-for-github-actio...

                              fun claims: https://github.com/github/actions-oidc-debugger#readme

                              • ashishb 3 months ago
                                Doable but I would prefer a complete isolation for simplicity.
                                • thund 3 months ago
                                  there are ways to isolate code from CI from CD, it's just not as easy as setting up the classic repo. One can use multiple repos for example, or run CI and CD with different products.
                              • nrvn 3 months ago
                                This is essentially how separation of duties(and concerns) looks like. And this is how some of the good examples of projects work. Specific techniques and tooling and specific boundaries of CI and CD vary depending on the nature of the end product but conceptually you are absolutely right.
                              • junto 3 months ago
                                They weren’t kidding on the response time. Very impressive from GitHub.
                                • belter 3 months ago
                                  Not very impressive to have an exposed public token with full write credentials...
                                  • toomuchtodo 3 months ago
                                    Perfect security does not exist. Their security system (people, tech) operated as expected with an impressive response time. Room for improvement, certainly, but there always is.

                                    Edit: Success is not the absence of vulnerability, but introduction, detection, and response trends.

                                    (Github enterprise comes out of my budget and I am responsible for appsec training and code IR, thoughts and opinions always my own)

                                    • timewizard 3 months ago
                                      > Perfect security does not exist.

                                      Having your CI/CD pipeline and your git repository service be so tightly bound creates security implications that do not need to exist.

                                      Further half the point of physical security is tamper evidence. Something entirely lost here.

                                      • belter 3 months ago
                                        > Their security system (people, tech) operated as expected

                                        You mean not finding the vulnerability in the first place?

                                        This would allow:

                                        - Compromise intellectual property by exfiltrating the source code of all private repositories using CodeQL.

                                        - Steal credentials within GitHub Actions secrets of any workflow job using CodeQL, and leverage those secrets to execute further supply chain attacks.

                                        - Execute code on internal infrastructure running CodeQL workflows.

                                        - Compromise GitHub Actions secrets of any workflow using the GitHub Actions Cache within a repo that uses CodeQL.

                                        >> Success is not the absence of vulnerability, but introduction, detection, and response trends.

                                        This isn’t a philosophy, it’s PR spin to reframe failure as progress...

                                        • koolba 3 months ago
                                          > Success is not the absence of vulnerability, but introduction, detection, and response trends.

                                          Don’t forget limitation of blast radius.

                                          When shit hits the proverbial fan, it’s helpful to limit the size of the room.

                                        • 1a527dd5 3 months ago
                                          Trying my best not to break the no snark rule [1], but I'm sure your code is 100% bullet proof against all current and future-yet-invented-attacks.

                                          [1] _and failing_.

                                          • atoav 3 months ago
                                            Nobody is immune against mistakes, but a certain class of mistakes¹ should never ever happen to anyone who should know better. And that in my book is anybody who has their code used by more people than themselves. I am not saying devs aren't allowed to make stupid mistakes, but if we let civil engineers have their bridges collapse with an "shit happens" -attitude trust in civil engineering would be questionable at best. So yeah shit happens to us devs, but we should be shamed if it was preventable by simply knowing the basics.

                                            So my opinion is anybody who writes code that is used by others should feel a certain danger-tingle whenever a secret or real user data is put literally anywhere.

                                            To all beginners that just means that when handling secrets, instead of pressing on, you should pause and make an exhaustive list of who would have read/write access to the secret under which conditions and whether that is intended. And with things that are world-readable like a public repo, this is especially crucial.

                                            Another one may or may not be your shells history, the context of your environment variables, whatever you copy-paste into the browser-searchbar/application/LLM/chat/comment section of your choice etc.

                                            If you absolutely have to store secrets/private user data in files within a repo it is a good idea to add the following to your .gitignore:

                                              *.private
                                              *.private.*
                                             
                                            And then every such file has to have ".private." within the filename (e.g. credentials.private.json), this not only marks it to yourself, it also prevents you to mix up critical with mundane configuration.

                                            But better is to spend a day to think about where secrets/user data really should be stored and how to manage them properly.

                                            ¹: a non-exhaustive list of other such mistakes: mistaking XOR for encryption, storing passwords in plaintext, using hardcoded credentials, relying on obscurity for security, sending data unencrypted over HTTP, not hashing passwords, using weak hash functions like MD5 or SHA-1, no input validation to stiff thst goes into your database, trusting user input blindly, buffer overflows due to unchecked input, lack of access control, no user authentication, using default admin credentials, running all code as administrator/root without dropping priviledges, relying on client-side validation for security, using self-rolled cryptographic algorithms, mixing authentication and authorization logic, no session expiration or timeout, predictable session IDs, no patch management or updates, wide-open network shares, exposing internal services to the internet, trusting data from cookies or query strings without verification, etc

                                            • belter 3 months ago
                                              [flagged]
                                        • helsinki 3 months ago
                                          As someone with the last name Prater—derived from Praetorian—I really wish I owned praetorian.com.
                                          • ratg13 3 months ago
                                            You would have had to have this thought prior to the release of the movie “The Net” in 1995
                                            • smoyer 3 months ago
                                              Their gokart project was awesome!
                                            • udev4096 3 months ago
                                              Using public github actions is just asking for trouble and more so without analyzing the workflow's procedure. Instead, just host one yourself using woodpecker or countless other great CI builders (circle, travis, gitlab, etc)
                                              • ryao 3 months ago
                                                I put CodeQL in use in OpenZFS PRs. This is not an issue for OpenZFS. None of our code is secret. :)
                                                • asmosoinio 3 months ago
                                                  I don't think this is a good take: Even if your code is not secret, the attack could add anything to your code or release artifacts.

                                                  Luckily it was quickly remedied at least.

                                                  • 3 months ago
                                                  • atxtechbro 3 months ago
                                                    Is this fixed?
                                                    • lsllc 3 months ago
                                                      It's in the article (and the comments here) -- yes, it was remediated within 3 hours of being reported back in January by GitHub.
                                                    • bloqs 3 months ago
                                                      This sites performance is so bad i can barely scroll