CVE-2019-1739 json
Cisco IOS and IOS XE Software Network-Based Application Recognition Denial of Service Vulnerabilities
published 2019-03-27 7 y ago modified 2026-06-17 4 mo ago also EUVD-2019-10296
- cvss
- 8.6
- version 3.0, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 2.5%
- EPSS 2.5% chance of exploitation in 30 days, percentile 84%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
Exploit prediction
2.52% chance of exploitation in the next 30 days, higher than 84% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.0 | 8.6 | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H |
| NVD | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVD | 2.0 | 7.8 | AV:N/AC:L/Au:N/C:N/I:N/A:C |
Affected products
- Cisco Cisco IOS and Cisco IOS-XE Software
Classification
- Weakness
-
- CWE-20 Improper Input Validation
- Technology feeds
References
-
tools.cisco.com
/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190327-nbar
vendor-advisory, patch
-
securityfocus.com
/bid/107597
vdb-entry, broken-link, third-party-advisory
Sources
- CVE List CVE-2019-1739
- NVD CVE-2019-1739
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