---
cve: "CVE-2021-21705"
severity: "MEDIUM"
cvss: 4.3
epss: "2.1%"
vendor: "PHP Group"
kev: false
exploited: false
published: "2021-10-04 04:15:08"
tags: [cve, security, medium]
source: tsecurity.de CVE-Dossier
exported: "2026-09-11T18:41:31+02:00"
---

# CVE-2021-21705

> 4.3 MEDIUM

## Beschreibung

In PHP versions 7.3.x below 7.3.29, 7.4.x below 7.4.21 and 8.0.x below 8.0.8, when using URL validation functionality via filter_var() function with FILTER_VALIDATE_URL parameter, an URL with invalid password field can be accepted as valid. This can lead to the code incorrectly parsing the URL and potentially leading to other security implications - like contacting a wrong server or making a wrong access decision.

## CVSS-Vektor

```
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Gering | bad |
| PR Privilegien | Keine | bad |
| UI Interaktion | Erforderlich | good |
| S Scope | Unverändert | good |
| C Vertraulichkeit | Gering | warn |
| I Integrität | Keine | good |
| A Verfügbarkeit | Keine | good |

## Patch verfügbar (OSV)

- 0960f2cdcf27e843ab5102559d291de9997739ea (Commit)
- bc008409dfa6a648671e4fde30b3a7acb374ec43 (Commit)

## Referenzen

- <https://bugs.php.net/bug.php?id=81122>
- <https://www.oracle.com/security-alerts/cpujan2022.html>
- <https://security.netapp.com/advisory/ntap-20211029-0006/>
- <https://security.gentoo.org/glsa/202209-20>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2021-21705) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_