---
cve: "CVE-2026-55068"
severity: "CRITICAL"
cvss: 9.3
epss: "0.6%"
vendor: "Free5Gc"
kev: false
exploited: false
published: "2026-08-28 16:57:12"
tags: [cve, security, critical]
source: tsecurity.de CVE-Dossier
exported: "2026-10-28T21:09:10+01:00"
---

# CVE-2026-55068

> 9.3 CRITICAL · 🧪 PoC

## Beschreibung

free5GC is an open-source implementation of the 5G core network. In 4.2.2 and earlier, the NRF RegisterNFInstance handler at PUT /nnrf-nfm/v1/nf-instances/{nfInstanceID} accepts NF Profiles without enforcing UUID format, nfStatus enum values, heartBeatTimer ranges, mandatory profile fields, or nfServices.ipEndPoints address constraints. The invalid profiles are persisted in the MongoDB NfProfile collection and returned by NFDiscover, allowing an attacker with SBI access to advertise attacker-controlled network-function endpoints and redirect control-plane signaling. This can expose credentials and signaling, alter service discovery integrity, and deny service across network functions that trust the NRF. This issue is fixed in version 4.2.3.

## CNA-Record (Kanon, cvelistV5)

- CNA: **GitHub_M**
- State: PUBLISHED
- Stand: 2026-08-31 18:56:29
- CNA-CVSS: **9.3** (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`)

## CISA-Anreicherung (vulnrichment/ADP)

- CISA-SSVC (Coordinator, v2.0.3):
  - Exploitation: **poc**
  - Automatable: **no**
  - Technical Impact: **total**

## CVSS-Vektor

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

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

## Schwachstellen-Klasse

- **CWE-20** — Improper Input Validation
  The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.

## Angriffsmuster (CAPEC)

- [CAPEC-10 — Buffer Overflow via Environment Variables](https://capec.mitre.org/data/definitions/10.html) _(Severity: High)_
- [CAPEC-13 — Subverting Environment Variable Values](https://capec.mitre.org/data/definitions/13.html) _(Severity: Very High)_
- [CAPEC-101 — Server Side Include (SSI) Injection](https://capec.mitre.org/data/definitions/101.html) _(Severity: High)_
- [CAPEC-104 — Cross Zone Scripting](https://capec.mitre.org/data/definitions/104.html) _(Severity: High)_
- [CAPEC-108 — Command Line Execution through SQL Injection](https://capec.mitre.org/data/definitions/108.html) _(Severity: Very High)_
- [CAPEC-109 — Object Relational Mapping Injection](https://capec.mitre.org/data/definitions/109.html) _(Severity: High)_
- [CAPEC-110 — SQL Injection through SOAP Parameter Tampering](https://capec.mitre.org/data/definitions/110.html) _(Severity: Very High)_
- [CAPEC-120 — Double Encoding](https://capec.mitre.org/data/definitions/120.html) _(Severity: Medium)_

## ATT&CK-Techniken

- [T1562.003 — Impair Defenses:Impair Command History Logging](https://attack.mitre.org/techniques/T1562/003/)
- [T1574.006 — Hijack Execution Flow:Dynamic Linker Hijacking](https://attack.mitre.org/techniques/T1574/006/)
- [T1574.007 — Hijack Execution Flow:Path Interception by PATH Environment ](https://attack.mitre.org/techniques/T1574/007/)

## Patch verfügbar (OSV)

- 3b34a08e93a9b334f0f4005d3a3a9f79b66d59b9 (Commit)
- bda0cf75be5556bb4c758c8b34710f3fe6bbe3ea (Commit)

## Referenzen

- <https://github.com/free5gc/free5gc/security/advisories/GHSA-x8mj-6p3q-g5pp>
- <https://github.com/free5gc/free5gc/issues/1056>
- <https://github.com/free5gc/nrf/pull/90>
- <https://github.com/free5gc/nrf/commit/bda0cf75be5556bb4c758c8b34710f3fe6bbe3ea>
- <https://github.com/free5gc/nrf/commit/fcd3cfaa27cc4dc17172ee0c4c3e0a3a696297c6>
- <https://github.com/free5gc/free5gc/releases/tag/v4.2.3>
- <https://github.com/free5gc/nrf/releases/tag/v1.4.5>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/sicherheitsluecken/cve-2026-55068/) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI WID (CSAF)_