---
cve: "CVE-2026-101087"
severity: "MEDIUM"
cvss: 5.3
epss: ""
vendor: "nezhahq"
kev: false
exploited: false
published: "2026-09-27 21:17:02"
tags: [cve, security, medium]
source: tsecurity.de CVE-Dossier
exported: "2026-09-29T06:26:17+02:00"
---

# CVE-2026-101087

> 5.3 MEDIUM · 🧪 PoC

## Beschreibung

Nezha versions 2.0.10 through 2.3.2 use a restricted HTTP client to validate user-configurable notification and DDNS webhook URLs, but the denylist did not cover IPv6 transition ranges — specifically the 6to4 prefix 2002::/16 and the local-use IPv4/IPv6 translation prefix 64:ff9b:1::/48. Because such addresses satisfy Go's netip.Addr.IsGlobalUnicast check, the URL validator accepted them. An authenticated user able to configure a webhook may be able to cause the dashboard to issue requests to an otherwise restricted IPv6 endpoint, but only where the dashboard's network provides unusual or non-standards-compliant routing for these transition ranges; no direct path to an IPv4 metadata, loopback, or private-network HTTP request has been demonstrated. The issue is fixed in version 2.3.3 (commit d1fcde8e), which blocks both prefixes.

## CNA-Record (Kanon, cvelistV5)

- CNA: **VulnCheck**
- State: PUBLISHED
- Stand: 2026-09-27 20:49:58
- CNA-CVSS: **5.3** (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:L/SI:L/SA:L`)

## CVSS-Vektor

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

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

## Patch verfügbar (OSV)

- 71d43c6a6e2c57784b1f744787bb6ee3475f3cbb (Commit)

## Referenzen

- <https://github.com/nezhahq/nezha/security/advisories/GHSA-jr2j-7hvh-h4q9>
- <https://github.com/nezhahq/nezha/commit/d1fcde8e>
- <https://www.vulncheck.com/advisories/nezha-2.0.10-through-2.3.2-ssrf-denylist-bypass-ipv6>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-101087) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI WID (CSAF)_