Security | Threat Detection | Cyberattacks | DevSecOps | Compliance

A browser agent in your cluster opens a supplier portal, screenshots it, and clicks somewhere the task never called for. The page looks exactly like the page the supplier serves, and to the person who checks it later, it still does. The classifier in front of the agent returned nothing, because the instruction that produced the click does not exist.

The blast radius of a prompt injection against your coding assistant was set weeks ago, by whoever built the dev environment image. Same assistant, same model, same injected sentence: on a laptop it collects every repository, SSH key and cloud login the developer holds; on a provisioned dev box it collects an organization token plus whatever the image left behind; on a CI runner it collects a deployment credential and a network path to production. Three environments, three incidents, one payload.

Every action in your agent-incident runbook operates on the agent. The payload of a RAG prompt injection sits in the index. You can kill the pod, rotate the credential and revoke the session, and each of those stops this workload from doing that thing again. None of them touch the chunk that caused it.

Tool output is untrusted because your own systems produce it. That is the part of the OWASP guidance that never makes it into a deployment. The label goes on web pages and email bodies, where an outsider obviously wrote the text. It never goes on the ticket store, the CRM, or the repo, because those are yours. The attacker does not care whose system it is. He cares which field takes free text: the ticket body, the opportunity note, the PR description.

Your coding agents run overnight on cloud dev boxes, with auto-approve on and an organization token in the environment, and the only thing standing between a public repository and that token is whatever the repository’s README tells the agent to do.

Prompt injection is three things happening at once. The definition written in 2022 described a model that followed an instruction hidden in the text it was asked to translate. The definition needed in 2026 describes an agent that read a support ticket and then queried a customer table it had never touched, using a service account nobody had revoked. Those are the same attack.

Prompt injection has not changed since 2022. What the model can do has. The instruction that hijacked a translation bot four years ago and the one that opened a homeowner’s windows last year are the same request: do something you are already allowed to do. The first system could only talk. The second could operate devices. Same sentence, different consequence. Here are ten real attacks, in order, and for each one the thing the system was allowed to do that made it work.

Prompt injection has a CWE, and the two incidents everyone cites were not filed under it. That is not a clerical detail. A CWE ID is a claim about root cause, and every entry carries a mitigation table that follows from the root cause it names. When a record says CWE-1427, it is saying the product failed to neutralise input before building a prompt, and it is implying that neutralising the input is the fix.

A prompt injection test suite can only report on the payloads it contains. That sentence is the whole problem with the number most teams have. Somewhere in a ticket there is a scan result: a scanner threw several hundred probes at the endpoint and a percentage got through. The percentage is real.

Here is a scene every security team knows. A reverse shell opens a connection to an external address, pulls a service-account token, and starts moving against your cloud identity. Two rows below it on the same dashboard sits a payload that hit a front-end container and never executed. Both are tagged high severity. Both are competing for the same analyst’s attention at the same moment.