CVE-2019-1836

Current Description

A vulnerability in the system shell for Cisco Nexus 9000 Series Fabric Switches in Application Centric Infrastructure (ACI) mode could allow an authenticated, local attacker to use symbolic links to overwrite system files. These system files may be sensitive and should not be overwritable by non-root users. The attacker would need valid device credentials. The vulnerability is due to incorrect symbolic link verification of directory paths when they are used in the system shell. An attacker could exploit this vulnerability by authenticating to the device and providing crafted user input to specific symbolic link CLI commands. Successful exploitation could allow the attacker to overwrite system files that should be restricted. This vulnerability has been fixed in software version 14.1(1i).

Basic Data

PublishedMay 03, 2019
Last ModifiedOctober 09, 2019
Assignercve@mitre.org
Data TypeCVE
Data FormatMITRE
Data Version4.0
Problem TypeCWE-22
CVE Data Version4.0

Base Metric V2

CVSS 2 - Version2.0
CVSS 2 - Vector StringAV:L/AC:L/Au:N/C:N/I:C/A:C
CVSS 2 - Access VectorLOCAL
CVSS 2 - Access ComplexityLOW
CVSS 2 - AuthenticationNONE
CVSS 2 - Confidentiality ImpactNONE
CVSS 2 - Availability ImpactCOMPLETE
CVSS 2 - Base Score6.6
SeverityMEDIUM
Exploitability Score3.9
Impact Score9.2
Obtain All Privilegefalse
Obtain User Privilegefalse
Obtain Other Privilegefalse

Base Metric V3

CVSS 3 - Version3.0
CVSS 3 - Vector StringCVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
CVSS 3 - Attack VectorLOCAL
CVSS 3 - Attack ComplexityLOW
CVSS 3 - Privileges RequiredLOW
CVSS 3 - User InteractionNONE
CVSS 3 - ScopeUNCHANGED
CVSS 3 - Confidentiality ImpactNONE
CVSS 3 - Integrity ImpactHIGH
CVSS 3 - Availability ImpactNONE
CVSS 3 - Base Score5.5
CVSS 3 - Base SeverityMEDIUM
Exploitability Score1.8
Base SeverityMEDIUM

Configurations

  • AND
    • OR - Configuration 1
      Cpe VersionPartVendorProductVersionUpdateEditionLanguageSW EditionTarget SWTarget HWOtherVersion Start IncludingVersion End IncludingVersion Start ExcludingVersion End Excluding
      2.3OSCiscoNx-os14.0(3d)*******
    • OR Running on/with:
      Cpe VersionPartVendorProductVersionUpdateEditionLanguageSW EditionTarget SWTarget HWOtherVersion Start IncludingVersion End IncludingVersion Start ExcludingVersion End Excluding
      2.3HardwareCiscoNexus 9300-*******
      2.3HardwareCiscoNexus 9500-*******

Vulnerable Software List

VendorProductVersions
Cisco Nx-os 14.0(3d)

References

NameSourceURLTags
108150http://www.securityfocus.com/bid/108150BIDThird Party Advisory VDB Entry
20190501 Cisco Nexus 9000 Series Fabric Switches Application Centric Infrastructure Mode Symbolic Link Path Traversal Vulnerabilityhttps://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190501-fabric-traveCISCOVendor Advisory