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

8.6 CVSS

Vulnerability 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.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

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Affected Vendor

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Affected Software

Cisco IOS and Cisco IOS-XE Software

Vulnerable Versions:

3.16.0S, 3.16.1S, 3.16.0aS, 3.16.1aS, 3.16.2S, 3.16.2aS, 3.16.0bS, 3.16.0cS, 3.16.3S, 3.16.2bS, 3.16.3aS, 3.16.4S, 3.16.4aS, 3.16.4bS, 3.16.4gS, 3.16.5S, 3.16.4cS, 3.16.4dS, 3.16.4eS, 3.16.5aS, 3.17.0S, 3.17.1S, 3.17.2S, 3.17.1aS, 3.17.3S, 3.17.4S, 3.2.0JA, 16.2.1, 16.2.2, 16.3.1, 16.3.2, 16.3.3, 16.3.1a, 16.3.4, 16.4.1, 16.4.2, 16.4.3, 16.5.1, 16.5.1a, 16.5.1b, 3.18.0aS, 3.18.0S, 3.18.1S, 3.18.2S, 3.18.3S, 3.18.4S, 3.18.0SP, 3.18.1SP, 3.18.1aSP, 3.18.1gSP, 3.18.1bSP, 3.18.1cSP, 3.18.2SP, 3.18.1hSP, 3.18.2aSP, 3.18.1iSP