# CVE-2023-20109: Cisco IOS and IOS XE Group Encrypted Transport VPN Out-of-Bounds Write Vulnerability

> CVE-2023-20109: Cisco IOS and IOS XE Group Encrypted Transport VPN Out-of-Bounds Write Vulnerability. CVSS 6.6 (CVSS 3.1), in CISA KEV.

Canonical: https://rewindex.com/cve/CVE-2023-20109
Last updated: 2025-10-21T23:05:36Z

- Published: 2023-09-27 17:23 UTC · Updated: 2025-10-21 23:05 UTC · Assigner: cisco
- CVSS: 6.6 (CVSS 3.1) · Severity: Medium · Vector: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H
- EPSS: 2.5%, 84th percentile (scored 2026-10-25)
- CISA KEV: yes, added 2023-10-10, federal due date 2023-10-31, ransomware use: Unknown
- CWE: CWE-787

## Description

A vulnerability in the Cisco Group Encrypted Transport VPN (GET VPN) feature of Cisco IOS Software and Cisco IOS XE Software could allow an authenticated, remote attacker who has administrative control of either a group member or a key server to execute arbitrary code on an affected device or cause the device to crash. 
 This vulnerability is due to insufficient validation of attributes in the Group Domain of Interpretation (GDOI) and G-IKEv2 protocols of the GET VPN feature. An attacker could exploit this vulnerability by either compromising an installed key server or modifying the configuration of a group member to point to a key server that is controlled by the attacker. A successful exploit could allow the attacker to execute arbitrary code and gain full control of the affected system or cause the affected system to reload, resulting in a denial of service (DoS) condition. For more information, see the Details \["\#details"\] section of this advisory.

## CISA required action

Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

## Affected vendors and products

- Cisco: Cisco IOS XE Software
- Cisco: IOS

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2023-20109)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2023-20109)
- [https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-getvpn-rce-g8qR68sx](https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-getvpn-rce-g8qR68sx)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2023-20109 · Markdown: https://rewindex.com/cve/CVE-2023-20109.md · JSON: https://rewindex.com/api/v1/cves/CVE-2023-20109 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T02:47:35.602Z