What is the severity of CVE-2019-1738?

CVE-2019-1738 has a high severity rating, allowing attackers to cause impacted devices to reload without authentication.

How do I fix CVE-2019-1738?

To fix CVE-2019-1738, upgrade your Cisco IOS Software to a version that addresses this vulnerability as outlined in Cisco's advisory.

What products are affected by CVE-2019-1738?

CVE-2019-1738 affects various versions of Cisco IOS and IOS XE software, specifically some versions in 15.1, 15.2, 15.3, 15.5, and 15.6.

Can CVE-2019-1738 be exploited remotely?

Yes, CVE-2019-1738 can be exploited remotely by unauthenticated attackers through crafted DNS packets.

What measures should I take regarding CVE-2019-1738?

Users should apply the recommended patches or update to secure software versions to mitigate the risks associated with CVE-2019-1738.

Vulnerability/
CVE-2019-1738

high

8.6

CWE

27/3/2019

21/11/2024

CVE-2019-1738: Cisco IOS and IOS XE Software Network-Based Application Recognition Denial of Service Vulnerability

First published: Wed Mar 27 2019(Updated: )

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 these vulnerabilities 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.

Credit: ykramarz@cisco.com

Affected Software	Affected Version	How to fix
Cisco IOS	=15.1\(2\)sg8a
Cisco IOS	=15.1\(3\)svg3d
Cisco IOS	=15.1\(3\)svi1b
Cisco IOS	=15.1\(3\)svk4b
Cisco IOS	=15.1\(3\)svk4c
Cisco IOS	=15.1\(3\)svm3
Cisco IOS	=15.1\(3\)svn2
Cisco IOS	=15.1\(3\)svo1
Cisco IOS	=15.1\(3\)svo2
Cisco IOS	=15.1\(3\)svo3
Cisco IOS	=15.1\(3\)svo4
Cisco IOS	=15.1\(3\)svp1
Cisco IOS	=15.1\(3\)svp2
Cisco IOS	=15.1\(4\)m12c
Cisco IOS	=15.2\(3\)ea1
Cisco IOS	=15.2\(4a\)ea5
Cisco IOS	=15.3\(3\)ja1n
Cisco IOS	=15.3\(3\)jd
Cisco IOS	=15.3\(3\)jd2
Cisco IOS	=15.3\(3\)jd3
Cisco IOS	=15.3\(3\)jd4
Cisco IOS	=15.3\(3\)jd5
Cisco IOS	=15.3\(3\)jd6
Cisco IOS	=15.3\(3\)jd7
Cisco IOS	=15.3\(3\)jd8
Cisco IOS	=15.3\(3\)jd9
Cisco IOS	=15.3\(3\)jd11
Cisco IOS	=15.3\(3\)jd12
Cisco IOS	=15.3\(3\)jd13
Cisco IOS	=15.3\(3\)jd14
Cisco IOS	=15.3\(3\)je
Cisco IOS	=15.3\(3\)jf
Cisco IOS	=15.3\(3\)jf1
Cisco IOS	=15.3\(3\)jf2
Cisco IOS	=15.3\(3\)jf4
Cisco IOS	=15.3\(3\)jf5
Cisco IOS	=15.3\(3\)jf35
Cisco IOS	=15.3\(3\)jg
Cisco IOS	=15.3\(3\)jg1
Cisco IOS	=15.3\(3\)jh
Cisco IOS	=15.3\(3\)ji
Cisco IOS	=15.3\(3\)ji2
Cisco IOS	=15.3\(3\)jnp
Cisco IOS	=15.3\(3\)jnp1
Cisco IOS	=15.3\(3\)jnp3
Cisco IOS	=15.3\(3\)jpb
Cisco IOS	=15.3\(3\)jpb1
Cisco IOS	=15.3\(3\)jpc
Cisco IOS	=15.3\(3\)jpc1
Cisco IOS	=15.3\(3\)jpc2
Cisco IOS	=15.3\(3\)jpc3
Cisco IOS	=15.3\(3\)jpc5
Cisco IOS	=15.3\(3\)jpd
Cisco IOS	=15.5\(3\)m
Cisco IOS	=15.5\(3\)m0a
Cisco IOS	=15.5\(3\)m1
Cisco IOS	=15.5\(3\)m2
Cisco IOS	=15.5\(3\)m2a
Cisco IOS	=15.5\(3\)m3
Cisco IOS	=15.5\(3\)m4
Cisco IOS	=15.5\(3\)m4a
Cisco IOS	=15.5\(3\)m4b
Cisco IOS	=15.5\(3\)m4c
Cisco IOS	=15.5\(3\)m5
Cisco IOS	=15.5\(3\)m5a
Cisco IOS	=15.5\(3\)s
Cisco IOS	=15.5\(3\)s0a
Cisco IOS	=15.5\(3\)s1
Cisco IOS	=15.5\(3\)s1a
Cisco IOS	=15.5\(3\)s2
Cisco IOS	=15.5\(3\)s3
Cisco IOS	=15.5\(3\)s4
Cisco IOS	=15.5\(3\)s5
Cisco IOS	=15.5\(3\)sn
Cisco IOS	=15.5\(3\)sn0a
Cisco IOS	=15.6\(1\)s
Cisco IOS	=15.6\(1\)s1
Cisco IOS	=15.6\(1\)s2
Cisco IOS	=15.6\(1\)s3
Cisco IOS	=15.6\(1\)s4
Cisco IOS	=15.6\(1\)sn
Cisco IOS	=15.6\(1\)sn1
Cisco IOS	=15.6\(1\)sn2
Cisco IOS	=15.6\(1\)sn3
Cisco IOS	=15.6\(1\)t
Cisco IOS	=15.6\(1\)t0a
Cisco IOS	=15.6\(1\)t1
Cisco IOS	=15.6\(1\)t2
Cisco IOS	=15.6\(2\)s
Cisco IOS	=15.6\(2\)s1
Cisco IOS	=15.6\(2\)s2
Cisco IOS	=15.6\(2\)s3
Cisco IOS	=15.6\(2\)s4
Cisco IOS	=15.6\(2\)sn
Cisco IOS	=15.6\(2\)sp3b
Cisco IOS	=15.6\(2\)t
Cisco IOS	=15.6\(2\)t0a
Cisco IOS	=15.6\(2\)t1
Cisco IOS	=15.6\(2\)t2
Cisco IOS	=15.6\(3\)m
Cisco IOS	=15.6\(3\)m0a
Cisco IOS	=15.6\(3\)m1
Cisco IOS	=15.6\(3\)m1a
Cisco IOS	=15.6\(3\)m1b
Cisco IOS	=15.6\(3\)sn
Cisco IOS	=15.6\(4\)sn
Cisco IOS	=15.6\(5\)sn
Cisco IOS	=15.6\(6\)sn
Cisco IOS	=15.6\(7\)sn
Cisco IOS XE Software	=3.2.0ja
Cisco IOS XE Software	=3.16.0as
Cisco IOS XE Software	=3.16.0bs
Cisco IOS XE Software	=3.16.0cs
Cisco IOS XE Software	=3.16.0s
Cisco IOS XE Software	=3.16.1as
Cisco IOS XE Software	=3.16.1s
Cisco IOS XE Software	=3.16.2as
Cisco IOS XE Software	=3.16.2bs
Cisco IOS XE Software	=3.16.2s
Cisco IOS XE Software	=3.16.3as
Cisco IOS XE Software	=3.16.3s
Cisco IOS XE Software	=3.16.4as
Cisco IOS XE Software	=3.16.4bs
Cisco IOS XE Software	=3.16.4cs
Cisco IOS XE Software	=3.16.4ds
Cisco IOS XE Software	=3.16.4es
Cisco IOS XE Software	=3.16.4gs
Cisco IOS XE Software	=3.16.4s
Cisco IOS XE Software	=3.16.5as
Cisco IOS XE Software	=3.16.5s
Cisco IOS XE Software	=3.17.0s
Cisco IOS XE Software	=3.17.1as
Cisco IOS XE Software	=3.17.1s
Cisco IOS XE Software	=3.17.3s
Cisco IOS XE Software	=3.17.4s
Cisco IOS XE Software	=3.18.0as
Cisco IOS XE Software	=3.18.0s
Cisco IOS XE Software	=3.18.0sp
Cisco IOS XE Software	=3.18.1asp
Cisco IOS XE Software	=3.18.1bsp
Cisco IOS XE Software	=3.18.1csp
Cisco IOS XE Software	=3.18.1gsp
Cisco IOS XE Software	=3.18.1hsp
Cisco IOS XE Software	=3.18.1isp
Cisco IOS XE Software	=3.18.1s
Cisco IOS XE Software	=3.18.1sp
Cisco IOS XE Software	=3.18.2asp
Cisco IOS XE Software	=3.18.2s
Cisco IOS XE Software	=3.18.2sp
Cisco IOS XE Software	=3.18.3s
Cisco IOS XE Software	=3.18.4s
Cisco IOS XE Software	=16.2.1
Cisco IOS XE Software	=16.2.2
Cisco IOS XE Software	=16.3.1
Cisco IOS XE Software	=16.3.1a
Cisco IOS XE Software	=16.3.2
Cisco IOS XE Software	=16.3.3
Cisco IOS XE Software	=16.3.4
Cisco IOS XE Software	=16.4.1
Cisco IOS XE Software	=16.4.2
Cisco IOS XE Software	=16.4.3
Cisco IOS XE Software	=16.5.1
Cisco IOS XE Software	=16.5.1a
Cisco IOS XE Software	=16.5.1b
Cisco IOS XE Software

Remedy

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190327-nbar

Never miss a vulnerability like this again

Reference Links

Frequently Asked Questions

What is the severity of CVE-2019-1738?
CVE-2019-1738 has a high severity rating, allowing attackers to cause impacted devices to reload without authentication.
How do I fix CVE-2019-1738?
To fix CVE-2019-1738, upgrade your Cisco IOS Software to a version that addresses this vulnerability as outlined in Cisco's advisory.
What products are affected by CVE-2019-1738?
CVE-2019-1738 affects various versions of Cisco IOS and IOS XE software, specifically some versions in 15.1, 15.2, 15.3, 15.5, and 15.6.
Can CVE-2019-1738 be exploited remotely?
Yes, CVE-2019-1738 can be exploited remotely by unauthenticated attackers through crafted DNS packets.
What measures should I take regarding CVE-2019-1738?
Users should apply the recommended patches or update to secure software versions to mitigate the risks associated with CVE-2019-1738.

agent/type
agent/references
agent/weakness
agent/remedy
agent/description
agent/title
agent/severity
agent/first-publish-date
collector/mitre-cve
source/MITRE
agent/last-modified-date
agent/event
agent/source
agent/author
agent/tags
agent/softwarecombine
collector/nvd-api
source/NVD
agent/software-canonical-lookup
agent/software-canonical-lookup-request
collector/nvd-index
vendor/cisco
canonical/cisco ios
version/cisco ios/15.1\(2\)sg8a
version/cisco ios/15.1\(3\)svg3d
version/cisco ios/15.1\(3\)svi1b
version/cisco ios/15.1\(3\)svk4b
version/cisco ios/15.1\(3\)svk4c
version/cisco ios/15.1\(3\)svm3
version/cisco ios/15.1\(3\)svn2
version/cisco ios/15.1\(3\)svo1
version/cisco ios/15.1\(3\)svo2
version/cisco ios/15.1\(3\)svo3
version/cisco ios/15.1\(3\)svo4
version/cisco ios/15.1\(3\)svp1
version/cisco ios/15.1\(3\)svp2
version/cisco ios/15.1\(4\)m12c
version/cisco ios/15.2\(3\)ea1
version/cisco ios/15.2\(4a\)ea5
version/cisco ios/15.3\(3\)ja1n
version/cisco ios/15.3\(3\)jd
version/cisco ios/15.3\(3\)jd2
version/cisco ios/15.3\(3\)jd3
version/cisco ios/15.3\(3\)jd4
version/cisco ios/15.3\(3\)jd5
version/cisco ios/15.3\(3\)jd6
version/cisco ios/15.3\(3\)jd7
version/cisco ios/15.3\(3\)jd8
version/cisco ios/15.3\(3\)jd9
version/cisco ios/15.3\(3\)jd11
version/cisco ios/15.3\(3\)jd12
version/cisco ios/15.3\(3\)jd13
version/cisco ios/15.3\(3\)jd14
version/cisco ios/15.3\(3\)je
version/cisco ios/15.3\(3\)jf
version/cisco ios/15.3\(3\)jf1
version/cisco ios/15.3\(3\)jf2
version/cisco ios/15.3\(3\)jf4
version/cisco ios/15.3\(3\)jf5
version/cisco ios/15.3\(3\)jf35
version/cisco ios/15.3\(3\)jg
version/cisco ios/15.3\(3\)jg1
version/cisco ios/15.3\(3\)jh
version/cisco ios/15.3\(3\)ji
version/cisco ios/15.3\(3\)ji2
version/cisco ios/15.3\(3\)jnp
version/cisco ios/15.3\(3\)jnp1
version/cisco ios/15.3\(3\)jnp3
version/cisco ios/15.3\(3\)jpb
version/cisco ios/15.3\(3\)jpb1
version/cisco ios/15.3\(3\)jpc
version/cisco ios/15.3\(3\)jpc1
version/cisco ios/15.3\(3\)jpc2
version/cisco ios/15.3\(3\)jpc3
version/cisco ios/15.3\(3\)jpc5
version/cisco ios/15.3\(3\)jpd
version/cisco ios/15.5\(3\)m
version/cisco ios/15.5\(3\)m0a
version/cisco ios/15.5\(3\)m1
version/cisco ios/15.5\(3\)m2
version/cisco ios/15.5\(3\)m2a
version/cisco ios/15.5\(3\)m3
version/cisco ios/15.5\(3\)m4
version/cisco ios/15.5\(3\)m4a
version/cisco ios/15.5\(3\)m4b
version/cisco ios/15.5\(3\)m4c
version/cisco ios/15.5\(3\)m5
version/cisco ios/15.5\(3\)m5a
version/cisco ios/15.5\(3\)s
version/cisco ios/15.5\(3\)s0a
version/cisco ios/15.5\(3\)s1
version/cisco ios/15.5\(3\)s1a
version/cisco ios/15.5\(3\)s2
version/cisco ios/15.5\(3\)s3
version/cisco ios/15.5\(3\)s4
version/cisco ios/15.5\(3\)s5
version/cisco ios/15.5\(3\)sn
version/cisco ios/15.5\(3\)sn0a
version/cisco ios/15.6\(1\)s
version/cisco ios/15.6\(1\)s1
version/cisco ios/15.6\(1\)s2
version/cisco ios/15.6\(1\)s3
version/cisco ios/15.6\(1\)s4
version/cisco ios/15.6\(1\)sn
version/cisco ios/15.6\(1\)sn1
version/cisco ios/15.6\(1\)sn2
version/cisco ios/15.6\(1\)sn3
version/cisco ios/15.6\(1\)t
version/cisco ios/15.6\(1\)t0a
version/cisco ios/15.6\(1\)t1
version/cisco ios/15.6\(1\)t2
version/cisco ios/15.6\(2\)s
version/cisco ios/15.6\(2\)s1
version/cisco ios/15.6\(2\)s2
version/cisco ios/15.6\(2\)s3
version/cisco ios/15.6\(2\)s4
version/cisco ios/15.6\(2\)sn
version/cisco ios/15.6\(2\)sp3b
version/cisco ios/15.6\(2\)t
version/cisco ios/15.6\(2\)t0a
version/cisco ios/15.6\(2\)t1
version/cisco ios/15.6\(2\)t2
version/cisco ios/15.6\(3\)m
version/cisco ios/15.6\(3\)m0a
version/cisco ios/15.6\(3\)m1
version/cisco ios/15.6\(3\)m1a
version/cisco ios/15.6\(3\)m1b
version/cisco ios/15.6\(3\)sn
version/cisco ios/15.6\(4\)sn
version/cisco ios/15.6\(5\)sn
version/cisco ios/15.6\(6\)sn
version/cisco ios/15.6\(7\)sn
canonical/cisco ios xe
version/cisco ios xe/3.2.0ja
version/cisco ios xe/3.16.0as
version/cisco ios xe/3.16.0bs
version/cisco ios xe/3.16.0cs
version/cisco ios xe/3.16.0s
version/cisco ios xe/3.16.1as
version/cisco ios xe/3.16.1s
version/cisco ios xe/3.16.2as
version/cisco ios xe/3.16.2bs
version/cisco ios xe/3.16.2s
version/cisco ios xe/3.16.3as
version/cisco ios xe/3.16.3s
version/cisco ios xe/3.16.4as
version/cisco ios xe/3.16.4bs
version/cisco ios xe/3.16.4cs
version/cisco ios xe/3.16.4ds
version/cisco ios xe/3.16.4es
version/cisco ios xe/3.16.4gs
version/cisco ios xe/3.16.4s
version/cisco ios xe/3.16.5as
version/cisco ios xe/3.16.5s
version/cisco ios xe/3.17.0s
version/cisco ios xe/3.17.1as
version/cisco ios xe/3.17.1s
version/cisco ios xe/3.17.3s
version/cisco ios xe/3.17.4s
version/cisco ios xe/3.18.0as
version/cisco ios xe/3.18.0s
version/cisco ios xe/3.18.0sp
version/cisco ios xe/3.18.1asp
version/cisco ios xe/3.18.1bsp
version/cisco ios xe/3.18.1csp
version/cisco ios xe/3.18.1gsp
version/cisco ios xe/3.18.1hsp
version/cisco ios xe/3.18.1isp
version/cisco ios xe/3.18.1s
version/cisco ios xe/3.18.1sp
version/cisco ios xe/3.18.2asp
version/cisco ios xe/3.18.2s
version/cisco ios xe/3.18.2sp
version/cisco ios xe/3.18.3s
version/cisco ios xe/3.18.4s
version/cisco ios xe/16.2.1
version/cisco ios xe/16.2.2
version/cisco ios xe/16.3.1
version/cisco ios xe/16.3.1a
version/cisco ios xe/16.3.2
version/cisco ios xe/16.3.3
version/cisco ios xe/16.3.4
version/cisco ios xe/16.4.1
version/cisco ios xe/16.4.2
version/cisco ios xe/16.4.3
version/cisco ios xe/16.5.1
version/cisco ios xe/16.5.1a
version/cisco ios xe/16.5.1b