Out Of Bounds Write in Adonisjs with Cockroachdb

An Out Of Bounds Write occurs when data is written to a memory location outside the intended allocation. In AdonisJS applications using CockroachDB, this typically manifests through unchecked user input used to size buffers, allocate arrays, or drive pagination logic that interfaces with CockroachDB. Because CockroachDB is compatible with PostgreSQL wire protocol, AdonisJS often interacts with it via node-postgres–style patterns where query results are mapped into JavaScript arrays or buffers. If a developer uses untrusted values (e.g., a query parameter like limit or page_size) to control buffer lengths or array allocations without validation, an attacker can supply values that cause writes beyond allocated memory boundaries.

Consider a route that accepts a chunk_size parameter to fetch rows from CockroachDB and store them in a fixed-length buffer before processing. In AdonisJS, this might look like constructing a buffer based on the parameter directly:

const chunkSize = parseInt(ctx.request.qs.chunk_size || '100');
const buffer = Buffer.alloc(chunkSize * 4); // assuming 4-byte integers
const { rows } = await db.query('SELECT id, value FROM items LIMIT $1', [chunkSize]);
for (let i = 0; i < rows.length; i++) {
  buffer.writeInt32LE(rows[i].value, i * 4);
}

If an attacker supplies a very large chunk_size, Buffer.alloc may succeed (due to memory availability), but the subsequent loop writes beyond the intended logical boundary when rows.length is smaller than chunkSize due to the LIMIT clause or actual data availability. This can corrupt adjacent memory, leading to undefined behavior, crashes, or potentially code execution in environments where memory layout is predictable. Even in a managed runtime like Node.js, such out-of-bounds writes can corrupt internal structures, causing crashes or information leaks.

Another common pattern involves dynamic array growth driven by unchecked input when interacting with CockroachDB. For example, using an unsanitized offset and limit to page through results can lead to excessive allocations if the values are large:

const offset = parseInt(ctx.request.qs.offset || '0');
const limit = parseInt(ctx.request.qs.limit || '10');
const items = await db.query('SELECT data FROM records ORDER BY id LIMIT $1 OFFSET $2', [limit, offset]);
const largeArray = new Array(limit);
items.rows.forEach((row, idx) => {
  largeArray[idx] = row.data;
});

If limit is uncontrolled, largeArray can demand excessive memory, indirectly stressing the runtime and potentially causing out-of-memory conditions that manifest as write faults in adjacent logical structures. CockroachDB’s consistent behavior under load means such issues might not surface in testing but can be triggered in production under specific workloads.

AdonisJS middleware that deserializes payloads into fixed-size structures also risks out-of-bounds writes if length checks are omitted. For instance, parsing a fixed-length binary protocol from a request body without verifying payload size before writing into a pre-allocated buffer can overflow when the body exceeds expectations. This is especially risky when the endpoint interfaces with CockroachDB for persistence, as unchecked data flows from the network through application logic into storage layers.

Because AdonisJS encourages structured query building, developers may assume ORM or query builder safeguards prevent injection, but input validation boundaries remain at the application layer. Out-of-bounds writes are not SQL injection; they are memory safety issues. However, an attacker could craft requests that manipulate memory and, in a compromised environment, influence SQL execution timing or error handling paths that involve CockroachDB responses.

To summarize, the combination of AdonisJS’s dynamic request handling and CockroachDB’s PostgreSQL compatibility can expose out-of-bounds writes when developers use untrusted input to control memory allocations, buffer sizes, or loop bounds. The risk is not in SQL injection but in improper input validation before memory operations, which can corrupt state or crash services.

Remediation centers on strict input validation, bounded memory operations, and defensive coding patterns when interacting with CockroachDB from AdonisJS. Always validate numeric parameters against reasonable ranges before using them for allocations or queries. For the chunk size example, enforce a maximum and ensure the buffer size matches actual data:

const MAX_CHUNK = 1000;
const chunkSize = Math.min(
  parseInt(ctx.request.qs.chunk_size || '100'),
  MAX_CHUNK
);
if (isNaN(chunkSize) || chunkSize <= 0) {
  throw new Error('Invalid chunk_size');
}
const buffer = Buffer.alloc(chunkSize * 4);
const { rows } = await db.query('SELECT id, value FROM items LIMIT $1', [chunkSize]);
for (let i = 0; i < rows.length; i++) { // use rows.length, not chunkSize
  buffer.writeInt32LE(rows[i].value, i * 4);
}

This ensures the buffer is sized to the actual data returned, preventing out-of-bounds writes even if a large chunk_size is requested. Additionally, validate offset and limit for pagination:

const MAX_LIMIT = 100;
const offset = Math.max(0, parseInt(ctx.request.qs.offset || '0'));
let limit = parseInt(ctx.request.qs.limit || '10');
if (isNaN(limit) || limit <= 0) limit = 10;
limit = Math.min(limit, MAX_LIMIT);
const items = await db.query('SELECT data FROM records ORDER BY id LIMIT $1 OFFSET $2', [limit, offset]);
const safeArray = items.rows.map(row => row.data); // avoid pre-allocating large arrays

Using .map avoids creating a large sparse array based on untrusted limits. For binary protocols, always verify payload length before writing into buffers:

const body = ctx.request.rawBody; // Uint8Array
const expectedLength = 24; // protocol header + payload size
if (body.length !== expectedLength) {
  throw new Error('Invalid payload length');
}
const header = body.slice(0, 8);
const payload = body.slice(8);
const value = payload.readInt32LE(0);
// safe processing

When using the middleBrick CLI to scan your AdonisJS endpoints, you can detect such risky patterns in unauthenticated scans:

npx middlebrick scan https://your-adonis-api.example.com

For teams integrating security into CI/CD, the middleBrick GitHub Action can fail builds if risk scores exceed your threshold, helping catch regressions that might reintroduce unsafe memory handling patterns before they reach production.

Finally, leverage the middleBrick Web Dashboard to track security scores over time and review detailed findings per category, ensuring that input validation and memory safety checks remain part of your ongoing posture when working with CockroachDB-backed AdonisJS services.