CVE-2018-0087: 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 serve...

Description

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.

Metrics

EPSS Probability

1.91%

77.2th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Cisco	Asyncos	10.5.1-296

References

http://www.securityfocus.com/bid/103407Third Party Advisory, VDB Entry
http://www.securitytracker.com/id/1040464Third Party Advisory, VDB Entry
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180307-wsaVendor Advisory
http://www.securityfocus.com/bid/103407Third Party Advisory, VDB Entry
http://www.securitytracker.com/id/1040464Third Party Advisory, VDB Entry
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180307-wsaVendor Advisory

Timeline

Published: Mar 8, 2018
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2018-0087?

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.

How severe is CVE-2018-0087?

Severity scoring for CVE-2018-0087 is pending analysis. The EPSS model estimates a 1.91% probability of exploitation in the next 30 days.

How do I fix CVE-2018-0087?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.