CVE-2023-20109

CVE-2023-20109 is a medium-severity vulnerability in Cisco Ios with a CVSS 3.x base score of 6.6. It is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming it has been exploited in the wild (added 2023-10-10). The underlying weakness is classified as CWE-787.

Key facts

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.

Frequently asked questions

What is CVE-2023-20109?
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.
How severe is CVE-2023-20109?
CVE-2023-20109 has a CVSS 3.x base score of 6.6, rated medium severity. It is exploitable over network with high attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2023-20109 being actively exploited?
Yes. CVE-2023-20109 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2023-10-10, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2023-20109?
CVE-2023-20109 primarily affects Cisco Ios. In total, 1038 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-20109?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.
Does CVE-2023-20109 have an EU (EUVD) identifier?
Yes. CVE-2023-20109 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-24288. It is also flagged as exploited in the EUVD (since 2023-10-10).
When was CVE-2023-20109 published?
CVE-2023-20109 was published on 2023-09-27 and last updated on 2026-06-17.

References

Affected products (1038)

More vulnerabilities in Cisco Ios

All CVEs affecting Cisco Ios →

Other CWE-787 (Out-of-bounds Write) vulnerabilities

Browse all CWE-787 (Out-of-bounds Write) vulnerabilities →