CVE-2018-15369: A vulnerability in the TACACS+ client subsystem of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cau...

Description

A vulnerability in the TACACS+ client subsystem of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a denial of service (DoS) condition. The vulnerability is due to improper handling of crafted TACACS+ response packets by the affected software. An attacker could exploit this vulnerability by injecting a crafted TACACS+ packet into an existing TACACS+ session between an affected device and a TACACS+ server or by impersonating a known, valid TACACS+ server and sending a crafted TACACS+ packet to an affected device when establishing a connection to the device. To exploit this vulnerability by using either method, the attacker must know the shared TACACS+ secret and the crafted packet must be sent in response to a TACACS+ request from a TACACS+ client. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition.

Metrics

EPSS Probability

2.06%

78.9th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Cisco	Ios	15.6\(1.9\)t
Cisco	Ios Xe	All versions

References

http://www.securityfocus.com/bid/105426Third Party Advisory, VDB Entry
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180926-tacplusVendor Advisory
http://www.securityfocus.com/bid/105426Third Party Advisory, VDB Entry
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180926-tacplusVendor Advisory

Timeline

Published: Oct 5, 2018
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2018-15369?

A vulnerability in the TACACS+ client subsystem of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a denial of service (DoS) condition. The vulnerability is due to improper handling of crafted TACACS+ response packets by the affected software. An attacker could exploit this vulnerability by injecting a crafted TACACS+ packet into an existing TACACS+ session between an affected device and a TACACS+ server or by impersonating a known, valid TACACS+ server and sending a crafted TACACS+ packet to an affected device when establishing a connection to the device. To exploit this vulnerability by using either method, the attacker must know the shared TACACS+ secret and the crafted packet must be sent in response to a TACACS+ request from a TACACS+ client. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition.

How severe is CVE-2018-15369?

Severity scoring for CVE-2018-15369 is pending analysis. The EPSS model estimates a 2.06% probability of exploitation in the next 30 days.

How do I fix CVE-2018-15369?

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.