CVE-2023-20109
Cisco IOS and IOS XE Group Encrypted Transport VPN Out-of-Bounds Write Vulnerability
What is affected
| Vendor | Cisco |
|---|---|
| Product | IOS and IOS XE |
| Weakness | CWE-787 |
The 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.
Required action
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
US federal civilian agencies were required to act by 31 October 2023 under BOD 22-01. The deadline is a compliance date, not a measure of severity — it says nothing about how dangerous the flaw is to anyone else.
Where this comes from
Every field on this page is taken from the CISA Known Exploited Vulnerabilities catalog, last synced 13 Nov 2026, 03:29. Nothing here is our own assessment. For the technical scoring, see the NVD record below.
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