HTTP Header Injection

Overview koa is a Koa web app framework Affected versions of this package are vulnerable to HTTP Header Injection via the hostname function in the. request.js file. An attacker can manipulate the value hostname by sending a specially crafted HTTP Host header containing an @ symbol, which can lead...

CVE-2026-27959

Koa is middleware for Node.js using ES2017 async functions. Prior to versions 3.1.2 and 2.16.4, Koa's ctx.hostname API performs naive parsing of the HTTP Host header, extracting everything before the first colon without validating the input conforms to RFC 3986 hostname syntax. When a malformed...

CVE-2026-27959 Koa has Host Header Injection via `ctx.hostname`

Koa is middleware for Node.js using ES2017 async functions. Prior to versions 3.1.2 and 2.16.4, Koa's ctx.hostname API performs naive parsing of the HTTP Host header, extracting everything before the first colon without validating the input conforms to RFC 3986 hostname syntax. When a malformed...