---
cve: "CVE-2026-56862"
severity: "HIGH"
cvss: 7.5
epss: "48%"
vendor: "Go standard library"
kev: false
exploited: false
published: "2026-08-13 22:17:22"
tags: [cve, security, high]
source: tsecurity.de CVE-Dossier
exported: "2026-09-03T04:55:01+02:00"
---

# CVE-2026-56862

> 7.5 HIGH

## Beschreibung

Handshake messages, such as KeyUpdate, are always considered as state-advancing, regardless of whether a handshake has been completed or not. As a result, a malicious client can keep sending KeyUpdate messages to force the server to keep performing key derivation operations indefinitely.

## CVSS-Vektor

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

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

## Referenzen

- <https://go.dev/issue/80528>
- <https://go.dev/cl/804261>
- <https://groups.google.com/g/golang-announce/c/94pEornpRlI>
- <https://pkg.go.dev/vuln/GO-2026-6090>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-56862) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_