The goal of Kerberoasting is to harvest TGS tickets for services that run on behalf of user accounts in the AD, not computer accounts. Thus, part of these TGS tickets is encrypted with keys derived from user passwords. As a consequence, their credentials could be cracked offline.
AI agents invoke Kerberoast to trigger actions in PentestMCP. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call — builds kicked off, notifications sent, workflows started.
Kerberoast triggers real processes with real consequences. An agent gone sideways doesn't fire it once — it starts dozens of builds, sends mass notifications, or burns through compute before anyone looks up.
Attacks that exploit this kind of access
The goal of Kerberoasting is to harvest TGS tickets for services that run on behalf of user accounts in the AD, not computer accounts. Thus, part of these TGS tickets is encrypted with keys derived from user passwords. As a consequence, their credentials could be cracked offline. It is categorised as a Execute tool in the PentestMCP MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.
Register the Pentest MCP server in PolicyLayer and add a rule for Kerberoast: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches PentestMCP. Nothing to install.
Kerberoast is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.
Yes. Add a rate_limit block to the Kerberoast rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.
Set action: deny in the PolicyLayer policy for Kerberoast. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.
Kerberoast is provided by the Pentest MCP server (youssefsahnoun/pentestmcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.