---
cve: "CVE-2024-6640"
severity: "MEDIUM"
cvss: 6.3
epss: "0.5%"
vendor: "FreeBSD"
kev: false
exploited: false
published: "2024-08-12 13:38:39"
tags: [cve, security, medium]
source: tsecurity.de CVE-Dossier
exported: "2026-11-09T05:40:01+01:00"
---

# CVE-2024-6640

> 6.3 MEDIUM

## Beschreibung

In ICMPv6 Neighbor Discovery (ND), the ID is always 0.  When pf is configured to allow ND and block incoming Echo Requests, a crafted Echo Request packet after a Neighbor Solicitation (NS) can trigger an Echo Reply.  The packet has to come from the same host as the NS and have a zero as identifier to match the state created by the Neighbor Discovery and allow replies to be generated.

ICMPv6 packets with identifier value of zero bypass firewall rules written on the assumption that the incoming packets are going to create a state in the state table.

## CNA-Record (Kanon, cvelistV5)

- CNA: **freebsd**
- State: PUBLISHED
- Stand: 2024-11-26 15:05:41

## CISA-Anreicherung (vulnrichment/ADP)

- CISA-SSVC (Coordinator, v2.0.3):
  - Exploitation: **none**
  - Automatable: **no**
  - Technical Impact: **partial**

## CVSS-Vektor

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

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

## Schwachstellen-Klasse

- **CWE-276** — Incorrect Default Permissions
  During installation, installed file permissions are set to allow anyone to modify those files.

## Angriffsmuster (CAPEC)

- [CAPEC-1 — Accessing Functionality Not Properly Constrained by ACLs](https://capec.mitre.org/data/definitions/1.html) _(Severity: High)_
- [CAPEC-81 — Web Server Logs Tampering](https://capec.mitre.org/data/definitions/81.html) _(Severity: High)_
- [CAPEC-127 — Directory Indexing](https://capec.mitre.org/data/definitions/127.html) _(Severity: Medium)_

## ATT&CK-Techniken

- [T1574.010 — Hijack Execution Flow: ServicesFile Permissions Weakness](https://attack.mitre.org/techniques/T1574/010/)
- [T1083 — File and Directory Discovery](https://attack.mitre.org/techniques/T1083/)

## BSI-Hinweise (deutsch)

- [FreeBSD Project FreeBSD OS: Mehrere Schwachstellen](https://wid.cert-bund.de/portal/wid/sicherheitshinweis/WID-SEC-W-2024-1793) — _BSI-Einstufung: hoch_
  Ein Angreifer kann mehrere Schwachstellen in FreeBSD Project FreeBSD OS ausnutzen, um Sicherheitsvorkehrungen zu umgehen, vertrauliche Informationen preiszugeben, Dateien zu verändern und beliebigen Code als root auszuführen.

## Referenzen

- <https://security.freebsd.org/advisories/FreeBSD-SA-24:05.pf.asc>
- <https://security.netapp.com/advisory/ntap-20240816-0008/>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/sicherheitsluecken/cve-2024-6640/) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI WID (CSAF)_