Zero-day vulnerability in Cisco IOS

Out-of-bounds write
CVE-2023-20109

Vulnerability details

Advisory: SB2023092914 - Remote code execution in Cisco IOS and IOS XE Software Cisco Group Encrypted Transport VPN Software

Vulnerable component: Cisco IOS

CVE-ID: CVE-2023-20109

CVSSv3 score: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H/E:H/RL:O/RC:C

CWE-ID: CWE-787 - Out-of-bounds write

Description:

The vulnerability allows a remote user to compromise vulnerable system.

The vulnerability exists due to insufficient validation of attributes in the Group Domain of Interpretation (GDOI) and G-IKEv2 protocols within the Cisco Group Encrypted Transport VPN (GET VPN) feature. A remote authenticated user with administrative control of either a group member or a key server can trigger an out-of-bounds write and execute arbitrary code on the target system.

Note, the vulnerability has been exploited in the wild.

External links:

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-getvpn-rce-g8qR68sx

About zero-day vulnerabilities

Zero-day vulnerability is an undisclosed vulnerability in software that hackers can exploit to compromise computer programs, gain unauthorized access to sensitive data, penetrate networks, etc. We consider vulnerability a zero-day when there is no solution provided from software vendor and the vulnerability is being actively exploited by malicious actors.

Zero-day candidate is a potential zero-day vulnerability in software which might have been used in targeted attacks, however there is no evidence to support this suggestion.