Stack Overflow Jobs is developed in partnership with Indeed.
Problems with a job listing, such as something that seems like a potential scam, can be reported directly on Indeed by clicking “Apply” from Stack Overflow Jobs, scrolling to the bottom of the job listing on Indeed, and then clicking the “Report job” button. For more information, see Indeed’s instructions here on how to report a job. No personal data about users is shared between Stack Overflow and Indeed when you report or apply for a job.
For more information on how to avoid fraudulent job listings, see Indeed’s Guidelines for a Safe Job Search.
Alternatively, if you come across a non-technical or off-topic job listing on Stack Overflow Jobs, you can raise that to SO staff directly. You can do this by creating a post on Meta Stack Exchange or Meta Stack Overflow tagged with support and stack-overflow-jobs. Staff will then investigate and take the necessary steps to get the job listing removed if necessary.