Overview
In the ever-evolving realm of cybersecurity, a new critical vulnerability, CVE-2025-20363, has been identified in several Cisco software products, including Cisco Secure Firewall Adaptive Security Appliance (ASA) Software, Cisco Secure Firewall Threat Defense (FTD) Software, Cisco IOS Software, Cisco IOS XE Software, and Cisco IOS XR Software. This vulnerability, if left unaddressed, allows an unauthenticated, remote attacker to execute arbitrary code on the affected device, potentially leading to a full system compromise.
This vulnerability is particularly noteworthy due to its high severity score and the widespread usage of the affected Cisco Software, which makes it a potential target for cybercriminals aiming to gain unauthorized access to networks and data. Mitigation and patching should be prioritized to prevent any possible exploitation.
Vulnerability Summary
CVE ID: CVE-2025-20363
Severity: Critical (CVSS: 9.0)
Attack Vector: Network
Privileges Required: None for Cisco ASA and FTD Software; Low for Cisco IOS, IOS XE, and IOS XR Software
User Interaction: None
Impact: Execution of arbitrary code as root, potentially leading to complete system compromise or data leakage
Affected Products
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Product | Affected Versions
Cisco Secure Firewall Adaptive Security Appliance (ASA) Software | All versions prior to patch
Cisco Secure Firewall Threat Defense (FTD) Software | All versions prior to patch
Cisco IOS Software | All versions prior to patch
Cisco IOS XE Software | All versions prior to patch
Cisco IOS XR Software | All versions prior to patch
How the Exploit Works
The vulnerability stems from the improper validation of user-supplied input in HTTP requests by the web services of the affected Cisco software. A successful exploit is achieved by an attacker sending a specially crafted HTTP request to a targeted web service on an affected device.
The attacker could potentially gain additional system information, overcome exploit mitigations, or both, thereby allowing them to execute arbitrary code as root. This could lead to the attacker gaining total control of the affected device.
Conceptual Example Code
Below is a conceptual example of how the vulnerability might be exploited via a malicious HTTP request:
POST /vulnerable/endpoint HTTP/1.1
Host: target.example.com
Content-Type: application/json
{ "malicious_payload": "base64_encoded_exploit_code_here" }In this example, a malicious payload is sent to a vulnerable endpoint on the target device. This payload, if processed by the vulnerable system, could lead to arbitrary code execution.
