---
cve: "CVE-2026-55090"
severity: "MEDIUM"
cvss: 5.3
epss: "54%"
vendor: "ether"
kev: false
exploited: false
published: "2026-08-19 20:17:18"
tags: [cve, security, medium]
source: tsecurity.de CVE-Dossier
exported: "2026-09-02T03:08:40+02:00"
---

# CVE-2026-55090

> 5.3 MEDIUM · 🧪 PoC

## Beschreibung

Etherpad is a real-time collaborative editor. Prior to 3.3.0, getHTMLFromAtext in src/node/utils/ExportHtml.ts interpolates values from the exportHtmlAdditionalTagsWithData plugin hook into span data attributes without HTML attribute escaping. A pad editor can place an attacker-controlled value into the attribute pool through moveOpsToNewPool and AttributePool.putAttrib. When a bundled plugin such as ep_font_color or ep_font_size registers the hook, opening the resulting HTML export causes the value to execute as stored cross-site scripting in the Etherpad origin. This issue is fixed in version 3.3.0.

## CVSS-Vektor

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

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

## Patch verfügbar (OSV)

- 86c56cf827dd6e5ff1b6cd3760f87adc47f58bb1 (Commit)
- 67f7d914f4e40f7cfda229c4865386deeb3c3c2b (Commit)

## Referenzen

- <https://github.com/ether/etherpad/security/advisories/GHSA-2jp7-wwpg-3p9w>
- <https://github.com/ether/etherpad/pull/7905>
- <https://github.com/ether/etherpad/commit/86c56cf827dd6e5ff1b6cd3760f87adc47f58bb1>
- <https://github.com/ether/etherpad/releases/tag/v3.3.0>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-55090) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_