Open Redirect Affecting koa-remove-trailing-slashes package, versions <2.0.2
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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Test your applications- Snyk IDSNYK-JS-KOAREMOVETRAILINGSLASHES-1085708
- published17 May 2021
- disclosed15 Mar 2021
- creditapple502j
Introduced: 15 Mar 2021
CVE-2021-23384 (opens in a new tab)How to fix?
Upgrade koa-remove-trailing-slashes to version 2.0.2 or higher.
Overview
koa-remove-trailing-slashes is a Koa middleware that makes sure all requests does not have trailing slashes
Affected versions of this package are vulnerable to Open Redirect via the use of trailing double slashes in the URL when accessing the vulnerable endpoint (such as https://example.com//attacker.example/). The vulnerable code is in index.js::removeTrailingSlashes(), as the web server uses relative URLs instead of absolute URLs.
PoC
// Run the code below to set up a vulnerable server instance // Then access http://localhost:3000///example.comconst Koa = require('koa'); const removeTrailingSlashes = require('koa-remove-trailing-slashes');
const app = new Koa();
app.use(removeTrailingSlashes());
app.use(ctx => { ctx.body = 'Hello World'; });
app.listen(3000);