CVE-2019-1740
Cisco IOS and IOS XE Software Network-Based Application Recognition Denial of Service Vulnerabilities
- Published
- Updated
- Reserved
- Assigned by
- cisco
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 are 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.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| ciscoCNA (assigner) | 3.0 | High8.6 | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H |
| NVDNVD · Modified | 3.1 | High8.6 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 2.2% · top 18% of all CVEs (5 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: yes · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.6.
Weakness
Affected products
Cisco · Cisco IOS and Cisco IOS-XE Software
- affected 3.16.0S
- affected 3.16.1S
- affected 3.16.0aS
- affected 3.16.1aS
- affected 3.16.2S
- affected 3.16.2aS
- affected 3.16.0bS
- affected 3.16.0cS
- affected 3.16.3S
- affected 3.16.2bS
- affected 3.16.3aS
- affected 3.16.4S
- affected 3.16.4aS
- affected 3.16.4bS
- affected 3.16.4gS
- affected 3.16.5S
- affected 3.16.4cS
- affected 3.16.4dS
- affected 3.16.4eS
- affected 3.16.5aS
- affected 3.17.0S
- affected 3.17.1S
- affected 3.17.2S
- affected 3.17.1aS
- affected 3.17.3S
- affected 3.17.4S
- affected 3.2.0JA
- affected 16.2.1
- affected 16.2.2
- affected 16.3.1
- affected 16.3.2
- affected 16.3.3
- affected 16.3.1a
- affected 16.3.4
- affected 16.4.1
- affected 16.4.2
- affected 16.4.3
- affected 16.5.1
- affected 16.5.1a
- affected 16.5.1b
- and 16 more
What to do
Exploitation: The Cisco Product Security Incident Response Team (PSIRT) is not aware of any public announcements or malicious use of the vulnerabilities that are described in this advisory.
References (2)
- 20190327 Cisco IOS and IOS XE Software Network-Based Application Recognition Denial of Service Vulnerabilities (opens in a new tab)vendor-advisoryx_refsource_CISCOx_transferred
- 107597 (opens in a new tab)vdb-entryx_refsource_BIDx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2019-1740)Record last updated .