nemu_write_memory
Write raw bytes into guest memory at a given address via base64 data. Use to update an input buffer between call_symbol invocations without re-allocating, or to patch code/data in place.
This record as markdown: /tools/io-github-vmoranv-jshookmcp/nemu-write-memory.md
What nemu_write_memory does on Jshookmcp
AI agents invoke nemu_write_memory to trigger actions in Jshookmcp. 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.
Why nemu_write_memory is rated High
Arbitrary memory writes enable code patching and can cause irreversible system compromise.
From the tool's definition Write raw bytes into guest memory, patch code/data in place
Attacks that exploit this kind of access
The rule that runs nemu_write_memory safely
PolicyLayer is an MCP gateway: it sits between your AI agents and Jshookmcp, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For nemu_write_memory, this is the rule to start with:
nemu_write_memory stays usable, but rate-capped: a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.
The button opens the PolicyLayer dashboard: create your workspace, connect Jshookmcp, apply this rule, and every nemu_write_memory call is checked against it from then on.
Questions about nemu_write_memory
Write raw bytes into guest memory at a given address via base64 data. Use to update an input buffer between call_symbol invocations without re-allocating, or to patch code/data in place. It is categorised as a Execute tool in the Jshookmcp MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.
Register the Jshook MCP server in PolicyLayer and add a rule for nemu_write_memory: 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 Jshookmcp. Nothing to install.
nemu_write_memory 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 nemu_write_memory 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 nemu_write_memory. 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.
nemu_write_memory is provided by the Jshook MCP server (@jshookmcp/jshook). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
More on Jshook, and thousands of servers like it.
Across the catalogue