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CVE-2019-1740

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

HIGH
8.6
CVSS Score
Published: March 27, 2019 at 11:25 PM UTC
Updated: June 17, 2026 at 02:29 AM UTC
2 products affected across 1 vendorIOSIOS Xe

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Severity
HIGH8.6
Exploit prediction
EPSS 2%
SSVC
No known exploit

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

IOS· Cisconpm
95%
15.3(3)jd15.3(3)jd1115.3(3)jd1215.3(3)jd1315.3(3)jd1415.3(3)jd215.3(3)jd315.3(3)jd415.3(3)jd515.3(3)jd615.3(3)jd715.3(3)jd815.3(3)jd915.3(3)je15.3(3)jf15.3(3)jf115.3(3)jf215.3(3)jf415.3(3)jf515.3(3)jg15.3(3)jg115.3(3)jh15.3(3)jk615.3(3)jnp15.3(3)jnp115.3(3)jnp315.3(3)jpb15.3(3)jpb115.3(3)jpc15.3(3)jpc115.3(3)jpc215.3(3)jpc315.3(3)jpc515.3(3)jpd15.5(3)m15.5(3)m0a15.5(3)m115.5(3)m215.5(3)m2a15.5(3)m315.5(3)m415.5(3)m4a15.5(3)m4b15.5(3)m4c15.5(3)m515.5(3)s15.5(3)s0a15.5(3)s115.5(3)s1a15.5(3)s215.5(3)s315.5(3)s415.5(3)s515.5(3)sn15.5(3)sn0a15.6(1)s15.6(1)s115.6(1)s215.6(1)s315.6(1)s415.6(1)sn15.6(1)sn115.6(1)sn215.6(1)sn315.6(1)t15.6(1)t0a15.6(1)t115.6(1)t215.6(2)s15.6(2)s115.6(2)s215.6(2)s315.6(2)s415.6(2)sn15.6(2)t15.6(2)t0a15.6(2)t115.6(2)t215.6(3)m15.6(3)m0a15.6(3)m115.6(3)m1a15.6(3)m1b15.6(3)sn15.6(4)sn15.6(5)sn15.6(6)sn15.6(7)sn15.6(7)sn115.6(7)sn215.6(7)sn3
IOS Xe· Cisco
95%
16.2.116.2.216.3.116.3.1a16.3.216.3.316.3.416.4.116.4.216.4.316.5.116.5.1a16.5.1b16.9.3s16.9.4c3.16.0S3.16.0aS3.16.0as3.16.0bS3.16.0bs3.16.0cS3.16.0cs3.16.0s3.16.1S3.16.1aS3.16.1as3.16.1s3.16.2S3.16.2aS3.16.2as3.16.2bS3.16.2bs3.16.2s3.16.3S3.16.3aS3.16.3as3.16.3s3.16.4S3.16.4aS3.16.4as3.16.4bS3.16.4bs3.16.4cS3.16.4cs3.16.4dS3.16.4ds3.16.4eS3.16.4es3.16.4gS3.16.4gs3.16.4s3.16.5S3.16.5aS3.16.5as3.16.5s3.17.0S3.17.0s3.17.1S3.17.1aS3.17.1as3.17.1s3.17.2S3.17.2s3.17.3S3.17.3s3.17.4S3.17.4s3.18.0S3.18.0SP3.18.0aS3.18.0as3.18.0s3.18.0sp3.18.1S3.18.1SP3.18.1aSP3.18.1asp3.18.1bSP3.18.1bsp3.18.1cSP3.18.1csp3.18.1gSP3.18.1gsp3.18.1hSP3.18.1hsp3.18.1iSP3.18.1isp3.18.1s3.18.1sp3.18.2S3.18.2SP3.18.2aSP3.18.2asp3.18.2s3.18.2sp3.18.3S3.18.3s3.18.4S3.18.4s3.2.0JA3.2.0ja

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

Patch and advisory references

References (2)

VDB Entryx_refsource_BIDThird Party Advisory
Source: [email protected]
http://www.securityfocus.com/bid/107597
Vendor Advisoryx_refsource_CISCOPatch
Source: [email protected]
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190327-nbar

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

8.6HIGH[email protected]
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
CHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-20

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