#VU29147 Input validation error in Cisco AsyncOS for Cisco Email Security Appliance - CVE-2020-3368

Vulnerability identifier: #VU29147

Vulnerability risk: Medium

CVSSv4.0: 2.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2020-3368

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Cisco AsyncOS for Cisco Email Security Appliance
Server applications / IDS/IPS systems, Firewalls and proxy servers

Vendor: Cisco Systems, Inc

Description

The vulnerability allows a remote attacker to bypass the URL reputation filters on an affected device.

The vulnerability exists due to insufficient validation of user-supplied input in the antispam protection mechanisms. A remote attacker can craft the URL in a particular way and bypass the URL reputation filters that are configured for the affected device, which could allow malicious URLs to pass through the device.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Cisco AsyncOS for Cisco Email Security Appliance: 12.1 089 - 12.5.0 066

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External links
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-esa-url-bypass-WO4BZ75s

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.