---
cve: "CVE-2023-36459"
severity: "CRITICAL"
cvss: 9.3
epss: "1.2%"
vendor: "mastodon"
kev: false
exploited: false
published: "2023-07-06 19:15:10"
tags: [cve, security, critical]
source: tsecurity.de CVE-Dossier
exported: "2026-09-18T05:39:52+02:00"
---

# CVE-2023-36459

> 9.3 CRITICAL · 🧪 PoC

## Beschreibung

Mastodon is a free, open-source social network server based on ActivityPub. Starting in version 1.3 and prior to versions 3.5.9, 4.0.5, and 4.1.3, an attacker using carefully crafted oEmbed data can bypass the HTML sanitization performed by Mastodon and include arbitrary HTML in oEmbed preview cards. This introduces a vector for cross-site scripting (XSS) payloads that can be rendered in the user's browser when a preview card for a malicious link is clicked through. Versions 3.5.9, 4.0.5, and 4.1.3 contain a patch for this issue.

## CVSS-Vektor

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

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

## Patch verfügbar (OSV)

- b10c974ba1952c545acff505bfd36feb0c60b000 (Commit)
- 8d7f6550f91338fb69e5c6e0cd28653122784665 (Commit)

## Referenzen

- <https://github.com/mastodon/mastodon/security/advisories/GHSA-ccm4-vgcc-73hp>
- <https://github.com/mastodon/mastodon/commit/6d8e0fae3e96f3cf4febe03fa7fcf5b95ff761b2>
- <https://github.com/mastodon/mastodon/releases/tag/v3.5.9>
- <https://github.com/mastodon/mastodon/releases/tag/v4.0.5>
- <https://github.com/mastodon/mastodon/releases/tag/v4.1.3>
- <http://www.openwall.com/lists/oss-security/2023/07/06/5>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2023-36459) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_