---
cve: "CVE-2026-40300"
severity: "MEDIUM"
cvss: 6.0
epss: "25%"
vendor: "zulip"
kev: false
exploited: false
published: "2026-05-12 17:16:20"
tags: [cve, security, medium]
source: tsecurity.de CVE-Dossier
exported: "2026-09-18T10:33:30+02:00"
---

# CVE-2026-40300

> 6.0 MEDIUM · 🧪 PoC

## Beschreibung

Zulip is an open-source team collaboration tool. Prior to 12.0, With message_edit_history_visibility_policy set to "moves", /api/v1/messages/{id}/history still returns historical content values, allowing low-privilege users to recover text that was edited away from other users' messages. This vulnerability is fixed in 12.0.

## CVSS-Vektor

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

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

## Patch verfügbar (OSV)

- 66114d404aeda6f3da1267469f3a5347acc8263a (Commit)

## Referenzen

- <https://github.com/zulip/zulip/security/advisories/GHSA-jp8f-mvv6-89cr>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-40300) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_