CVE-2026-27959 - CERT CVE
ID CVE-2026-27959
Sažetak 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 Host header containing a `@` symbol is received, `ctx.hostname` returns `evil[.]com` - an attacker-controlled value. Applications using `ctx.hostname` for URL generation, password reset links, email verification URLs, or routing decisions are vulnerable to Host header injection attacks. Versions 3.1.2 and 2.16.4 fix the issue.
Reference
CVSS
Base: 7.5
Impact: 3.6
Exploitability:3.9
Pristup
VektorSloženostAutentikacija
NETWORK LOW NONE
Impact
PovjerljivostCjelovitostDostupnost
NONE HIGH NONE
CVSS vektor CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Zadnje važnije ažuriranje 28-02-2026 - 00:55
Objavljeno 26-02-2026 - 02:16