---
cve: "CVE-2025-25200"
severity: "CRITICAL"
cvss: 9.2
epss: "0.8%"
vendor: "koajs"
kev: false
exploited: false
published: "2025-02-12 18:15:28"
tags: [cve, security, critical]
source: tsecurity.de CVE-Dossier
exported: "2026-11-09T15:03:32+01:00"
---

# CVE-2025-25200

> 9.2 CRITICAL · 🧪 PoC

## Beschreibung

Koa is expressive middleware for Node.js using ES2017 async functions. Prior to versions 0.21.2, 1.7.1, 2.15.4, and 3.0.0-alpha.3, Koa uses an evil regex to parse the `X-Forwarded-Proto` and `X-Forwarded-Host` HTTP headers. This can be exploited to carry out a Denial-of-Service attack. Versions 0.21.2, 1.7.1, 2.15.4, and 3.0.0-alpha.3 fix the issue.

## CNA-Record (Kanon, cvelistV5)

- CNA: **GitHub_M**
- State: PUBLISHED
- Stand: 2025-02-12 19:29:10
- CNA-CVSS: **9.2** (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H`)

## CISA-Anreicherung (vulnrichment/ADP)

- CISA-SSVC (Coordinator, v2.0.3):
  - Exploitation: **none**
  - Automatable: **no**
  - Technical Impact: **partial**

## CVSS-Vektor

```
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Gering | bad |
| PR Privilegien | Keine | bad |
| UI Interaktion | Keine | bad |

## Schwachstellen-Klasse

- **CWE-1333** — Inefficient Regular Expression Complexity
  The product uses a regular expression with a worst-case computational complexity that is inefficient and possibly exponential.

## Angriffsmuster (CAPEC)

- [CAPEC-492 — Regular Expression Exponential Blowup](https://capec.mitre.org/data/definitions/492.html)

## Patch verfügbar (OSV)

- 93fe903fc966635a991bcf890cfc3427d33a1a08 (Commit)
- 5f294bb1c7c8d9c61904378d250439a321bffd32 (Commit)

## Referenzen

- <https://github.com/koajs/koa/security/advisories/GHSA-593f-38f6-jp5m>
- <https://github.com/koajs/koa/commit/5054af6e31ffd451a4151a1fe144cef6e5d0d83c>
- <https://github.com/koajs/koa/commit/5f294bb1c7c8d9c61904378d250439a321bffd32>
- <https://github.com/koajs/koa/commit/93fe903fc966635a991bcf890cfc3427d33a1a08>
- <https://github.com/koajs/koa/blob/master/lib/request.js#L259>
- <https://github.com/koajs/koa/blob/master/lib/request.js#L404>
- <https://github.com/koajs/koa/releases/tag/2.15.4>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/sicherheitsluecken/cve-2025-25200/) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI WID (CSAF)_