Arbitrary Code Exec in Cisco IOS GET VPN via GDOI
CVE-2023-20109 Published on September 27, 2023

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.

NVD

Known Exploited Vulnerability

This Cisco IOS and IOS XE Group Encrypted Transport VPN Out-of-Bounds Write Vulnerability is part of CISA's list of Known Exploited Vulnerabilities. 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.

The following remediation steps are recommended / required by October 31, 2023: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

Vulnerability Analysis

CVE-2023-20109 can be exploited with network access, and requires user privileges. This vulnerability is consided to have a high level of attack complexity. This vulnerability is known to be actively exploited by threat actors. The potential impact of an exploit of this vulnerability is considered to be very high.

Attack Vector:
NETWORK
Attack Complexity:
HIGH
Privileges Required:
HIGH
User Interaction:
NONE
Scope:
UNCHANGED
Confidentiality Impact:
HIGH
Integrity Impact:
HIGH
Availability Impact:
HIGH

Weakness Type

What is a Memory Corruption Vulnerability?

The software writes data past the end, or before the beginning, of the intended buffer. Typically, this can result in corruption of data, a crash, or code execution. The software may modify an index or perform pointer arithmetic that references a memory location that is outside of the boundaries of the buffer. A subsequent write operation then produces undefined or unexpected results.

CVE-2023-20109 has been classified to as a Memory Corruption vulnerability or weakness.


Products Associated with CVE-2023-20109

You can be notified by email with stack.watch whenever vulnerabilities like CVE-2023-20109 are published in these products:

Cisco Internetwork Operating System (IOS)
 
Cisco IOS XE
 

Affected Versions

Cisco IOS: Cisco IOS XE Software:

Exploit Probability

EPSS
0.58%
Percentile
68.37%

EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.