Cisco Asyncos vulnerabilities
56 vulnerabilities
Known vulnerabilities in Cisco Asyncos, newest first, with CVSS severity, EPSS, KEV listings, ransomware use and the affected versions.
CVE-2026-76519ciscoasyncos+1KEV
EPSS score1.57%
A vulnerability in the Advanced Malware Protection (AMP) feature of Cisco Secure Email Gateway could allow an unauthenticated, remote attacker to write arbitrary files on the underlying operating system.
This vulnerability is due to improper handling of email attachments when the file reputation service is enabled. An attacker could exploit this vulnerability by sending an email that contains a crafted attachment through an affected device. A successful exploit could allow the attacker to write arbitrary files and execute commands with root privileges on the underlying operating system.CVE-2018-0087ciscoasyncosEPSS score1.84%
A vulnerability in the FTP server of the Cisco Web Security Appliance (WSA) could allow an unauthenticated, remote attacker to log in to the FTP server of the device without a valid password. The attacker does need to have a valid username. The vulnerability is due to incorrect FTP user credential validation. An attacker could exploit this vulnerability by using FTP to connect to the management IP address of the targeted device. A successful exploit could allow the attacker to log in to the FTP server of the Cisco WSA without having a valid password. This vulnerability affects Cisco AsyncOS for WSA Software on both virtual and hardware appliances that are running any release of Cisco AsyncOS 10.5.1 for WSA Software. The device is vulnerable only if FTP is enabled on the management interface. FTP is disabled by default. Cisco Bug IDs: CSCvf74281.CVE-2018-0095ciscoasyncosEPSS score0.40%
A vulnerability in the administrative shell of Cisco AsyncOS on Cisco Email Security Appliance (ESA) and Content Security Management Appliance (SMA) could allow an authenticated, local attacker to escalate their privilege level and gain root access. The attacker has to have a valid user credential with at least a privilege level of a guest user. The vulnerability is due to an incorrect networking configuration at the administrative shell CLI. An attacker could exploit this vulnerability by authenticating to the targeted device and issuing a set of crafted, malicious commands at the administrative shell. An exploit could allow the attacker to gain root access on the device. Cisco Bug IDs: CSCvb34303, CSCvb35726.CVE-2018-15460ciscoasyncos+1EPSS score2.52%
A vulnerability in the email message filtering feature of Cisco AsyncOS Software for Cisco Email Security Appliances (ESA) could allow an unauthenticated, remote attacker to cause the CPU utilization to increase to 100 percent, causing a denial of service (DoS) condition on an affected device. The vulnerability is due to improper filtering of email messages that contain references to whitelisted URLs. An attacker could exploit this vulnerability by sending a malicious email message that contains a large number of whitelisted URLs. A successful exploit could allow the attacker to cause a sustained DoS condition that could force the affected device to stop scanning and forwarding email messages.CVE-2021-1359ciscoasyncos+2EPSS score1.88%
A vulnerability in the configuration management of Cisco AsyncOS for Cisco Web Security Appliance (WSA) could allow an authenticated, remote attacker to perform command injection and elevate privileges to root. This vulnerability is due to insufficient validation of user-supplied XML input for the web interface. An attacker could exploit this vulnerability by uploading crafted XML configuration files that contain scripting code to a vulnerable device. A successful exploit could allow the attacker to execute arbitrary commands on the underlying operating system and elevate privileges to root. An attacker would need a valid user account with the rights to upload configuration files to exploit this vulnerability.CVE-2021-1566ciscoasyncos+3EPSS score0.67%
A vulnerability in the Cisco Advanced Malware Protection (AMP) for Endpoints integration of Cisco AsyncOS for Cisco Email Security Appliance (ESA) and Cisco Web Security Appliance (WSA) could allow an unauthenticated, remote attacker to intercept traffic between an affected device and the AMP servers. This vulnerability is due to improper certificate validation when an affected device establishes TLS connections. A man-in-the-middle attacker could exploit this vulnerability by sending a crafted TLS packet to an affected device. A successful exploit could allow the attacker to spoof a trusted host and then extract sensitive information or alter certain API requests.CVE-2021-1534ciscoasyncos+1EPSS score1.07%
A vulnerability in the antispam protection mechanisms of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to bypass the URL reputation filters on an affected device. This vulnerability is due to improper processing of URLs. An attacker could exploit this vulnerability by crafting a URL in a particular way. A successful exploit could allow the attacker to bypass the URL reputation filters that are configured for an affected device, which could allow malicious URLs to pass through the device.CVE-2021-1425ciscoasyncos+1EPSS score0.53%
A vulnerability in the web-based management interface of Cisco AsyncOS Software for Cisco Content Security Management Appliance (SMA) could allow an authenticated, remote attacker to access sensitive information on an affected device.
The vulnerability exists because confidential information is being included in HTTP requests that are exchanged between the user and the device. An attacker could exploit this vulnerability by looking at the raw HTTP requests that are sent to the interface. A successful exploit could allow the attacker to obtain some of the passwords that are configured throughout the interface.Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.CVE-2021-34698ciscoasyncos+1EPSS score1.43%
A vulnerability in the proxy service of Cisco AsyncOS for Cisco Web Security Appliance (WSA) could allow an unauthenticated, remote attacker to exhaust system memory and cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper memory management in the proxy service of an affected device. An attacker could exploit this vulnerability by establishing a large number of HTTPS connections to the affected device. A successful exploit could allow the attacker to cause the system to stop processing new connections, which could result in a DoS condition. Note: Manual intervention may be required to recover from this situation.CVE-2021-34741ciscoasyncos+1EPSS score1.29%
A vulnerability in the email scanning algorithm of Cisco AsyncOS software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to perform a denial of service (DoS) attack against an affected device. This vulnerability is due to insufficient input validation of incoming emails. An attacker could exploit this vulnerability by sending a crafted email through Cisco ESA. A successful exploit could allow the attacker to exhaust all the available CPU resources on an affected device for an extended period of time, preventing other emails from being processed and resulting in a DoS condition.CVE-2015-0577ciscoasyncosEPSS score1.16%
Multiple cross-site scripting (XSS) vulnerabilities in the IronPort Spam Quarantine (ISQ) page in Cisco AsyncOS, as used on the Cisco Email Security Appliance (ESA) and Content Security Management Appliance (SMA), allow remote attackers to inject arbitrary web script or HTML via unspecified parameters, aka Bug IDs CSCus22925 and CSCup08113.CVE-2015-0605ciscoasyncosEPSS score1.22%
The uuencode inspection engine in Cisco AsyncOS on Cisco Email Security Appliance (ESA) devices 8.5 and earlier allows remote attackers to bypass intended content restrictions via a crafted e-mail attachment with uuencode encoding, aka Bug ID CSCzv54343.CVE-2016-1461ciscoasyncosEPSS score2.35%
Cisco AsyncOS on Email Security Appliance (ESA) devices through 9.7.0-125 allows remote attackers to bypass malware detection via a crafted attachment in an e-mail message, aka Bug ID CSCuz14932.CVE-2016-1438ciscoasyncosEPSS score1.22%
Cisco AsyncOS 9.7.0-125 on Email Security Appliance (ESA) devices allows remote attackers to bypass intended spam filtering via crafted executable content in a ZIP archive, aka Bug ID CSCuy39210.CVE-2025-20185ciscoasyncos+3EPSS score0.19%
A vulnerability in the implementation of the remote access functionality of Cisco AsyncOS Software for Cisco Secure Email and Web Manager, Cisco Secure Email Gateway, and Cisco Secure Web Appliance could allow an authenticated, local attacker to elevate privileges to root. The attacker must authenticate with valid administrator credentials.
This vulnerability is due to an architectural flaw in the password generation algorithm for the remote access functionality. An attacker could exploit this vulnerability by generating a temporary password for the service account. A successful exploit could allow the attacker to execute arbitrary commands as root and access the underlying operating system.
Note: The Security Impact Rating (SIR) for this vulnerability is Medium due to the unrestricted scope of information that is accessible to an attacker.CVE-2025-20183ciscoasyncos+1EPSS score0.44%
A vulnerability in a policy-based Cisco Application Visibility and Control (AVC) implementation of Cisco AsyncOS Software for Cisco Secure Web Appliance could allow an unauthenticated, remote attacker to evade the antivirus scanner and download a malicious file onto an endpoint.
The vulnerability is due to improper handling of a crafted range request header. An attacker could exploit this vulnerability by sending an HTTP request with a crafted range request header through the affected device. A successful exploit could allow the attacker to evade the antivirus scanner and download malware onto the endpoint without detection by Cisco Secure Web Appliance.CVE-2025-20180ciscoasyncos+2EPSS score0.32%
A vulnerability in the web-based management interface of Cisco AsyncOS Software for Cisco Secure Email and Web Manager and Secure Email Gateway could allow an authenticated, remote attacker to conduct a stored cross-site scripting (XSS) attack against a user of the interface.
This vulnerability is due to insufficient validation of user input. An attacker could exploit this vulnerability by persuading a user of an affected interface to click a crafted link. A successful exploit could allow the attacker to execute arbitrary script code in the context of the affected interface or access sensitive, browser-based information. To exploit this vulnerability, the attacker must have valid credentials for a user account with at least the role of Operator.CVE-2025-20184ciscoasyncos+2EPSS score0.86%
A vulnerability in the web-based management interface of Cisco AsyncOS Software for Cisco Secure Email Gateway and Cisco Secure Web Appliance could allow an authenticated, remote attacker to perform command injection attacks against an affected device. The attacker must authenticate with valid administrator credentials.
This vulnerability is due to insufficient validation of XML configuration files by an affected device. An attacker could exploit this vulnerability by uploading a crafted XML configuration file. A successful exploit could allow the attacker to inject commands to the underlying operating system with root privileges.CVE-2025-20393ciscoasyncos+2KEVEPSS score32.39%
A vulnerability in the Spam Quarantine feature of Cisco AsyncOS Software for Cisco Secure Email Gateway and Cisco Secure Email and Web Manager could allow an unauthenticated, remote attacker to execute arbitrary system commands on an affected device with root privileges.
This vulnerability is due to insufficient validation of HTTP requests by the Spam Quarantine feature. An attacker could exploit this vulnerability by sending a crafted HTTP request to the affected device. A successful exploit could allow the attacker to execute arbitrary commands on the underlying operating system with root privileges.CVE-2020-26082ciscoasyncos+1EPSS score0.63%
A vulnerability in the zip decompression engine of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to bypass content filters that are configured on an affected device.
The vulnerability is due to improper handling of password-protected zip files. An attacker could exploit this vulnerability by sending a malicious file inside a crafted zip-compressed file to an affected device. A successful exploit could allow the attacker to bypass configured content filters that would normally drop the email.