CVE-2022-20871 in Secure Web Appliance
Summary
by MITRE • 11/15/2024
A vulnerability in the web management interface of Cisco AsyncOS for Cisco Secure Web Appliance, formerly Cisco Web Security Appliance (WSA), could allow an authenticated, remote attacker to perform a command injection and elevate privileges to root. This vulnerability is due to insufficient validation of user-supplied input for the web interface. An attacker could exploit this vulnerability by authenticating to the system and sending a crafted HTTP packet to the affected device. A successful exploit could allow the attacker to execute arbitrary commands on the underlying operating system and elevate privileges to root. To successfully exploit this vulnerability, an attacker would need at least read-only credentials.Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.Attention: Simplifying the Cisco portfolio includes the renaming of security products under one brand: Cisco Secure. For more information, see .
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Analysis
by VulDB Data Team • 08/11/2025
This vulnerability resides within the web management interface of Cisco AsyncOS for Cisco Secure Web Appliance, formerly known as Cisco Web Security Appliance, representing a critical command injection flaw that enables authenticated remote attackers to achieve root privilege escalation. The vulnerability stems from inadequate input validation mechanisms within the web interface components, specifically failing to properly sanitize user-supplied data before processing. This weakness creates an avenue for attackers to manipulate the system through crafted HTTP requests that bypass normal security controls. The flaw is particularly concerning as it requires only read-only credentials for exploitation, making it accessible to users with minimal privileges who can leverage this vulnerability to gain complete system control.
The technical implementation of this vulnerability aligns with CWE-77 and CWE-78 categories, which specifically address command injection flaws where user input is directly incorporated into system commands without proper sanitization. The attack vector involves an authenticated session where an attacker sends malicious HTTP requests containing specially crafted payloads that exploit the insufficient input validation. When the system processes these requests, the malformed input gets executed as system commands, allowing arbitrary code execution on the underlying operating system. This command injection occurs at the web interface layer, where user-supplied parameters are not adequately validated or escaped before being passed to system-level functions.
The operational impact of this vulnerability extends beyond simple privilege escalation to encompass complete system compromise and potential data exfiltration. Successful exploitation enables attackers to execute commands with root privileges, providing them with unrestricted access to all system resources, files, and network interfaces. This elevation of privileges allows for persistent access, system modification, and potential lateral movement within the network. The vulnerability's remote exploitation capability means attackers can compromise systems without physical access, while the requirement for only read-only credentials makes it particularly dangerous as it can be exploited by insiders or compromised low-privilege accounts. Organizations using affected Cisco Secure Web Appliances face significant risk of unauthorized system access and potential breach of sensitive network traffic data.
Cisco has addressed this vulnerability through official software updates that implement proper input validation and sanitization measures to prevent the injection of malicious commands. The company has not provided any workarounds as the fix requires modifications to the core validation mechanisms within the web interface. Security practitioners should prioritize immediate deployment of these updates across all affected devices to mitigate the risk of exploitation. The vulnerability demonstrates the importance of implementing robust input validation at all levels of application interfaces, particularly in management systems where authentication is required. Organizations should also implement network segmentation and monitoring to detect unusual command execution patterns that might indicate exploitation attempts, while maintaining comprehensive audit logs for security incident response and forensic analysis. This vulnerability serves as a reminder of the critical need for defense-in-depth strategies and regular security assessments of management interfaces to prevent similar command injection attacks from compromising enterprise security infrastructure.