CVE-2023-20109
Published: October 10, 2023
Official Description
Cisco IOS and IOS XE contain an out-of-bounds write vulnerability in the Group Encrypted Transport VPN (GET VPN) feature that could allow an authenticated, remote attacker who has administrative control of either a group member or a key server to execute malicious code or cause a device to crash.
CISA KEV Advisory
Cisco IOS and IOS XE Group Encrypted Transport VPN Out-of-Bounds Write Vulnerability
Cisco IOS and IOS XE contain an out-of-bounds write vulnerability in the Group Encrypted Transport VPN (GET VPN) feature that could allow an authenticated, remote attacker who has administrative control of either a group member or a key server to execute malicious code or cause a device to crash.
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
Risk Analysis
This vulnerability in Cisco IOS and IOS XE's Group Encrypted Transport VPN (GET VPN) feature allows an authenticated, remote administrator to potentially execute malicious code or crash a device. The high severity and confirmed exploitation in the wild (KEV) make this an urgent concern, despite a relatively low EPSS score.
This vulnerability is actively being exploited in the wild, as confirmed by its presence in CISA's KEV catalog. Exploitation requires administrative control of a group member or key server.
Administrators should apply available patches or upgrades for Cisco IOS and IOS XE to address this out-of-bounds write vulnerability. Reviewing and restricting administrative access to GET VPN components is also recommended.
Technical Analysis
CVE-2023-20109 requires local access, meaning attackers must already have a foothold on the target system.
Exploitation requires some privileges, which limits the exposure to scenarios where an attacker has already gained initial access.
CISA has added CVE-2023-20109 to the Known Exploited Vulnerabilities (KEV) catalog, confirming active exploitation in the wild. U.S. federal agencies are required to patch this within the mandated timeframe, and all organizations should treat remediation as urgent.
Affected Vendors & Products
Exploit & PoC Resources
All References (2)
Quick Facts
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2023-20109 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts
- !CISA KEV: Federal agencies must patch per BOD 22-01 timeline
- !Active exploitation confirmed — treat as P1