CVE-2019-1739

Cisco IOS and IOS XE Software Network-Based Application Recognition Denial of Service Vulnerabilities

Description

A vulnerability in the Network-Based Application Recognition (NBAR) feature of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload. This vulnerability is due to a parsing issue on DNS packets. An attacker could exploit this vulnerability by sending crafted DNS packets through routers that are running an affected version and have NBAR enabled. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a denial of service (DoS) condition.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 3.0 •
CVSS 2.0 •
EPSS 2.06% Top 20%
Vendor Advisory cisco.com
Affected: Cisco Cisco IOS and Cisco IOS-XE Software
Published at:
Updated at:

References

Link Tags
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190327-nbar patch vendor advisory
http://www.securityfocus.com/bid/107597 broken link third party advisory vdb entry

Frequently Asked Questions

What is the severity of CVE-2019-1739?
CVE-2019-1739 has been scored as a high severity vulnerability.
How to fix CVE-2019-1739?
To fix CVE-2019-1739, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2019-1739 being actively exploited in the wild?
It is possible that CVE-2019-1739 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~2% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2019-1739?
CVE-2019-1739 affects Cisco Cisco IOS and Cisco IOS-XE Software.
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