---
cve: "CVE-2026-42556"
severity: "HIGH"
cvss: 8.9
epss: "26%"
vendor: "gitroomhq"
kev: false
exploited: false
published: "2026-05-08 23:16:39"
tags: [cve, security, high]
source: tsecurity.de CVE-Dossier
exported: "2026-09-12T20:34:02+02:00"
---

# CVE-2026-42556

> 8.9 HIGH · 🧪 PoC

## Beschreibung

Postiz is an AI social media scheduling tool. From version 2.21.6 to before version 2.21.7, any authenticated user who can create a post can store arbitrary HTML in post content by tampering their own save request and send the public preview link /p/?share=true to another user. The preview page renders that stored HTML with dangerouslySetInnerHTML on the main application origin. This issue has been patched in version 2.21.7.

## CVSS-Vektor

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

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

## Patch verfügbar (OSV)

- 7236213ea4520bd67b45688c2787d1f4586b3b51 (Commit)

## Referenzen

- <https://github.com/gitroomhq/postiz-app/security/advisories/GHSA-hhxq-3wg7-4rj8>
- <https://github.com/gitroomhq/postiz-app/releases/tag/v2.21.7>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-42556) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_