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cisco

asyncos

44 known vulnerabilities · sorted by CVSS score

CVE-2025-20393
CRITICAL10.0

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.

cisco / asyncos+5
Network
Published Dec 17, 2025
Page 1 of 3
CVE-2019-15956
HIGH8.8

A vulnerability in the web management interface of Cisco AsyncOS Software for Cisco Web Security Appliance (WSA) could allow an authenticated, remote attacker to perform an unauthorized system reset on an affected device. The vulnerability is due to improper authorization controls for a specific URL in the web management interface. An attacker could exploit this vulnerability by sending a crafted HTTP request to an affected device. A successful exploit could have a twofold impact: the attacker could either change the administrator password, gaining privileged access, or reset the network configuration details, causing a denial of service (DoS) condition. In both scenarios, manual intervention is required to restore normal operations.

cisco / asyncos+5
Network
Published Nov 26, 2019
CVE-2024-20435
HIGH8.8

A vulnerability in the CLI of Cisco AsyncOS for Secure Web Appliance could allow an authenticated, local attacker to execute arbitrary commands and elevate privileges to root. This vulnerability is due to insufficient validation of user-supplied input for the CLI. An attacker could exploit this vulnerability by authenticating to the system and executing a crafted command on 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 guest credentials.

cisco / asyncos+26
Local
Published Jul 17, 2024
CVE-2019-1947
HIGH8.6

A vulnerability in the email message filtering feature of Cisco AsyncOS Software for Cisco Email Security Appliance (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 handling of email messages that contain large attachments. An attacker could exploit this vulnerability by sending a malicious email message through the targeted device. A successful exploit could allow the attacker to cause a permanent DoS condition due to high CPU utilization. This vulnerability may require manual intervention to recover the ESA.

cisco / email_security_appliance+1
Network
Published Sep 23, 2020
CVE-2018-15460
HIGH8.6

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.

cisco / asyncos+1
Network
Published Jan 10, 2019
CVE-2021-34698
HIGH8.6

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.

cisco / asyncos+2
Network
Published Oct 6, 2021
CVE-2019-1886
HIGH8.6

A vulnerability in the HTTPS decryption feature of Cisco Web Security Appliance (WSA) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to insufficient validation of Secure Sockets Layer (SSL) server certificates. An attacker could exploit this vulnerability by installing a malformed certificate in a web server and sending a request to it through the Cisco WSA. A successful exploit could allow the attacker to cause an unexpected restart of the proxy process on an affected device.

cisco / asyncos+4
Network
Published Jul 4, 2019
CVE-2020-3367
HIGH7.8

A vulnerability in the log subscription subsystem of Cisco AsyncOS for the Cisco Secure Web Appliance (formerly Web Security Appliance) could allow an authenticated, local attacker to perform command injection and elevate privileges to root. This vulnerability is due to insufficient validation of user-supplied input for the web interface and CLI. An attacker could exploit this vulnerability by authenticating to the affected device and injecting scripting commands in the scope of the log subscription subsystem. A successful exploit could allow the attacker to execute arbitrary commands on the underlying operating system and elevate privileges to root.

cisco / asyncos+3
Local
Published Nov 18, 2020
CVE-2018-0095
HIGH7.8

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.

cisco / asyncos+1
Local
Published Jan 18, 2018
CVE-2019-1884
HIGH7.7

A vulnerability in the web proxy functionality of Cisco AsyncOS Software for Cisco Web Security Appliance (WSA) could allow an authenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to insufficient input validation mechanisms for certain fields in HTTP/HTTPS requests sent through an affected device. A successful attacker could exploit this vulnerability by sending a malicious HTTP/HTTPS request through an affected device. An exploit could allow the attacker to force the device to stop processing traffic, resulting in a DoS condition.

cisco / asyncos+6
Network
Published Jul 4, 2019
CVE-2022-20653
HIGH7.5

A vulnerability in the DNS-based Authentication of Named Entities (DANE) email verification component of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient error handling in DNS name resolution by the affected software. An attacker could exploit this vulnerability by sending specially formatted email messages that are processed by an affected device. A successful exploit could allow the attacker to cause the device to become unreachable from management interfaces or to process additional email messages for a period of time until the device recovers, resulting in a DoS condition. Continued attacks could cause the device to become completely unavailable, resulting in a persistent DoS condition.

cisco / asyncos+2
Network
Published Feb 17, 2022
CVE-2021-34741
HIGH7.5

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.

cisco / asyncos+2
Network
Published Nov 4, 2021
CVE-2021-1566
HIGH7.4

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.

cisco / email_security_appliance+11
Network
Published Jun 16, 2021
CVE-2022-20942
MEDIUM6.5

A vulnerability in the web-based management interface of Cisco Email Security Appliance (ESA), Cisco Secure Email and Web Manager, and Cisco Secure Web Appliance, formerly known as Cisco Web Security Appliance (WSA), could allow an authenticated, remote attacker to retrieve sensitive information from an affected device, including user credentials. This vulnerability is due to weak enforcement of back-end authorization checks. An attacker could exploit this vulnerability by sending a crafted HTTP request to an affected device. A successful exploit could allow the attacker to obtain confidential data that is stored on the affected device.

cisco / asyncos+6
Network
Published Nov 4, 2022
CVE-2025-20184
MEDIUM6.5

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.

cisco / asyncos+67
Network
Published Feb 5, 2025
CVE-2024-20429
MEDIUM6.5

A vulnerability in the web-based management interface of Cisco AsyncOS for Secure Email Gateway could allow an authenticated, remote attacker to execute arbitrary system commands on an affected device. This vulnerability is due to insufficient input validation in certain portions of the web-based management interface. 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. To successfully exploit this vulnerability, an attacker would need at least valid Operator credentials.

cisco / asyncos+17
Network
Published Jul 17, 2024
CVE-2022-20871
MEDIUM6.3

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 .

cisco / asyncos+10
Network
Published Nov 15, 2024
CVE-2021-1359
MEDIUM6.3

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.

cisco / web_security_appliance+3
Network
Published Jul 8, 2021
CVE-2024-20258
MEDIUM6.1

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 unauthenticated, remote attacker to conduct an 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.

cisco / asyncos+2
Network
Published May 15, 2024
CVE-2024-20392
MEDIUM6.1

A vulnerability in the web-based management API of Cisco AsyncOS Software for Cisco Secure Email Gateway could allow an unauthenticated, remote attacker to conduct an HTTP response splitting attack. This vulnerability is due to insufficient input validation of some parameters that are passed to the web-based management API of the affected system. 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 perform cross-site scripting (XSS) attacks, resulting in the execution of arbitrary script code in the browser of the targeted user, or could allow the attacker to access sensitive, browser-based information.

cisco / asyncos+20
Network
Published May 15, 2024