---
cve: "CVE-2026-20272"
severity: "CRITICAL"
cvss: 9.8
epss: "36%"
vendor: "Cisco"
kev: false
exploited: false
published: "2026-08-05 17:16:49"
tags: [cve, security, critical]
source: tsecurity.de CVE-Dossier
exported: "2026-09-06T20:02:13+02:00"
---

# CVE-2026-20272

> 9.8 CRITICAL

## Beschreibung

As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco IOS XE Software engineering team has conducted a comprehensive internal security review. This review resulted in software hardening releases that address multiple internally discovered vulnerabilities.

The vulnerabilities tracked by CVE-2026-20272 are related to issues with improper neutralization of special elements that are grouped under the Common Weakness Enumeration (CWE) Pillar CWE-74.

## CVSS-Vektor

```
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/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 | Hoch | bad |
| I Integrität | Hoch | bad |
| A Verfügbarkeit | Hoch | bad |

## Schwachstellen-Klasse

- **CWE-74** — Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')
  The product constructs all or part of a command, data structure, or record using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify how it is parsed or interpreted when it is sent to a downstream component.

## 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-14 — Client-side Injection-induced Buffer Overflow](https://capec.mitre.org/data/definitions/14.html) _(Severity: High)_
- [CAPEC-101 — Server Side Include (SSI) Injection](https://capec.mitre.org/data/definitions/101.html) _(Severity: High)_
- [CAPEC-105 — HTTP Request Splitting](https://capec.mitre.org/data/definitions/105.html) _(Severity: High)_
- [CAPEC-108 — Command Line Execution through SQL Injection](https://capec.mitre.org/data/definitions/108.html) _(Severity: Very High)_
- [CAPEC-120 — Double Encoding](https://capec.mitre.org/data/definitions/120.html) _(Severity: Medium)_
- [CAPEC-135 — Format String Injection](https://capec.mitre.org/data/definitions/135.html) _(Severity: High)_

## 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/)

## Referenzen

- <https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-hardening-iosxe-V8NMuMZJ>
- <https://www.cve.org/Media/News/item/blog/2026/06/16/Preserving-Vulnerability-Level-Identification>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-20272) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_