TL;DR: AI runtime security is the control layer that catches prompt injection, data leakage, and rogue tool calls only visible once an agent is running, not during pre-deployment scans, according to Highflame. The core issue is assumption collapse: safe lab results do not prove safe production behaviour, especially when agents act through live prompts, tool calls, and delegated identity.
NHIMG editorial — based on content published by Highflame: AI runtime security closes the gap build-time scans miss
Questions worth separating out
Q: What breaks when AI agent controls are only applied at build time?
A: Buildtime checks alone do not stop a deployed agent from drifting into unsafe behavior during execution.
Q: Why do AI agents need request-time authorization instead of session approval?
A: Because the risky decision is often the next action, not the overall session.
Q: What signals show that AI runtime controls are failing?
A: Warning signs include unexplained tool usage, access to data outside the expected workflow, repeated policy overrides, and behavioural drift across sessions.
Practitioner guidance
- Enforce request-time authorization for every agent action Check each prompt, tool call, and agent-to-agent hop against policy before execution, so approval is tied to the current context rather than the session as a whole.
- Scope agent identities to short-lived, task-bound credentials Bind each agent to narrowly scoped credentials with minimal delegation so any harvested secret has limited reach and a short usable life.
- Add live detection to the decision path Feed injection patterns, anomalous call sequences, and sensitive-data signals into the same control that evaluates the next action, not a downstream review queue.
What's in the full article
Highflame's full article covers the operational detail this post intentionally leaves for the source:
- Inline enforcement examples for prompt, tool, and agent-to-agent requests
- The vendor's view of how runtime policy, detection, and revocation work together in practice
- A comparison of build-time AI security and runtime controls across live traffic paths
- Implementation context for teams deciding where runtime checks should sit in the request path
👉 Read Highflame's analysis of AI runtime security and production agent risk →
AI runtime security: are your production controls keeping up?
Explore further
Build-time approval is not a proxy for production safety: The article is right to separate pre-deployment testing from runtime control, because the attack only exists once the agent is consuming live input. Build-time scanning can tell you that a model or app compiled successfully, but it cannot answer whether the next tool call is appropriate. The implication for identity programmes is that runtime authorisation must sit alongside pre-release assurance, not behind it.
A few things that frame the scale:
- The average estimated time to remediate a leaked secret is 27 days, despite 75% of organisations expressing strong confidence in their secrets management capabilities, according to The State of Secrets in AppSec.
- Only 44% of developers are reported to follow security best practices for secrets management, exposing a significant developer behaviour gap.
A question worth separating out:
Q: Who is accountable when an AI agent uses delegated access incorrectly?
A: Accountability should follow the delegated authority chain, not stop at the agent label. The relevant owners are the teams responsible for the human identity, the service identity, the workflow, and the policy that allowed the action path. If those responsibilities are not explicit, incident review will be incomplete and remediation will focus on the wrong layer.
👉 Read our full editorial: AI runtime security closes the gap build-time scans miss