CVE-2019-1842

mediumpriority · track · 22EPSS 0.012 · 68 %ileEURUUS
grimoire priorityP3 · Track
Exploitable?
—
no known exploitation
Likely / severe?
1.19% (68th) EPSS
CVSS 5.5 · medium
Is it mine?
9 products
Check your exposure
Who says so?
5 sources
cnnvd · enisa_euvd · fstec_bdu · cisco_csaf

EPSS · scored 2026-10-27

A vulnerability in the Secure Shell (SSH) authentication function of Cisco IOS XR Software could allow an authenticated, remote attacker to successfully log in to an affected device using two distinct usernames. The vulnerability is due to a logic error that may occur when certain sequences of actions are processed during an SSH login event on the affected device. An attacker could exploit this vulnerability by initiating an SSH session to the device with a specific sequence that presents the two usernames. A successful exploit could result in logging data misrepresentation, user enumeration, or, in certain circumstances, a command authorization bypass. See the Details section for more information.

01

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

02

cvss

Technical severity, 0–10. One row per scoring source.

5.5
010

base score 0–10 · higher = more severe · hover a vector to decode

v2.05.5mediumAV:N/AC:L/Au:S/C:P/I:P/A:Nprimary · NVD / NIST USexploitability 8 · impact 4.9
v3.15.4mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:Nprimary · NVD / NIST USexploitability 2.8 · impact 2.5
v3.05.4mediumCVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:Nsecondary · ENISA EU
v3.05.4mediumCVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:Nsecondary · psirt@cisco.com USexploitability 2.8 · impact 2.5
v3.05.4mediumCVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:Nsecondary · Cisco PSIRT US
v3.15.4mediumAV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:Nsecondary · FSTEC (BDU) RU
v3.15mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N/E:Usecondary · CVSS-BT (t0sche)
03

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Trackcoordinatorcisa_ssvcUS
04

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-287USprimaryCWE-285USCWE-285US
05

affected products (9)

Products and version ranges known to be affected.

06

advisories (1)

Vendor and ecosystem advisories describing this.

  • cisco-sa-20190605-iosxr-sshCisco IOS XR Software Secure Shell Authentication Vulnerability2019-06-05csaf · cisco_csafUS

    A vulnerability in the Secure Shell (SSH) authentication function of Cisco IOS XR Software could allow an authenticated, remote attacker to successfully log in to an affected device using two distinct usernames. The vulnerability is due to a logic error that may occur when certain sequences of actions are processed during an SSH login event on the affected device. An attacker could exploit this vulnerability by initiating an SSH session to the device with a specific sequence that presents the two usernames. A successful exploit could result in logging data misrepresentation, user enumeration, or, in certain circumstances, a command authorization bypass. See the Details ["#details"] section for more information. There are no workarounds that address this vulnerability. This advisory is available at the following link: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190605-iosxr-ssh ["https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190605-iosxr-ssh"]

07

also known as (4)

Other names and identifiers for this entity.

08

sources

Which sources assert this record, and when.

cnnvdenisa_euvdfstec_bducisco_csafnvdNVDCVE.orgMITRE
published 2019-06-05modified 2026-06-17
10

references (10)

External citations — patches, advisories, analysis.

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