cbcvebase.
CVE-2023-20046
published 2023-05-09

CVE-2023-20046: A vulnerability in the key-based SSH authentication feature of Cisco StarOS Software could allow an authenticated, remote attacker to elevate privileges on an…

PriorityP260high8.8CVSS 3.1
AVNACLPRLUINSUCHIHAH
EPSS
0.86%
54.3th percentile
A vulnerability in the key-based SSH authentication feature of Cisco StarOS Software could allow an authenticated, remote attacker to elevate privileges on an affected device. This vulnerability is due to insufficient validation of user-supplied credentials. An attacker could exploit this vulnerability by sending a valid low-privileged SSH key to an affected device from a host that has an IP address that is configured as the source for a high-privileged user account. A successful exploit could allow the attacker to log in to the affected device through SSH as a high-privileged user. There are workarounds that address this vulnerability.

Affected

416 ranges· showing 25
VendorProductVersion rangeFixed in
ciscocisco_asr_5000_series_software
ciscocisco_asr_5000_series_software
ciscocisco_asr_5000_series_software
ciscocisco_asr_5000_series_software
ciscocisco_asr_5000_series_software
ciscocisco_asr_5000_series_software
ciscocisco_asr_5000_series_software
ciscocisco_asr_5000_series_software
ciscocisco_asr_5000_series_software
ciscocisco_asr_5000_series_software
ciscocisco_asr_5000_series_software
ciscocisco_asr_5000_series_software
ciscocisco_asr_5000_series_software
ciscocisco_asr_5000_series_software
ciscocisco_asr_5000_series_software
ciscocisco_asr_5000_series_software
ciscocisco_asr_5000_series_software
ciscocisco_asr_5000_series_software
ciscocisco_asr_5000_series_software
ciscocisco_asr_5000_series_software
ciscocisco_asr_5000_series_software
ciscocisco_asr_5000_series_software
ciscocisco_asr_5000_series_software
ciscocisco_asr_5000_series_software
ciscocisco_asr_5000_series_software

Detection & IOCsextracted from sources · hover to see the quote

  • Attacker exploits SSH key-based authentication by sending a valid low-privileged SSH key from a source IP configured for a high-privileged user account, resulting in privilege escalation login via SSH
  • Monitor for SSH logins to Cisco StarOS devices where the authenticating SSH key belongs to a low-privileged user but the resulting session is granted high-privileged access
  • Track Cisco internal bug ID CSCwd89468 for patch and indicator correlation related to this vulnerability
  • ·The vulnerability is triggered only when an attacker's source IP address matches one configured as the source for a high-privileged user account on the device; review StarOS SSH source-IP-to-user mappings for misconfigurations or abuse
  • ·Workarounds exist and should be applied if patching is not immediately possible; consult the Cisco advisory for specific workaround steps
  • ·Root cause is insufficient validation of user-supplied credentials (CWE-289 Authentication Bypass by Alternate Name); the device does not properly validate that the SSH key presented corresponds to the privilege level of the authenticated user

CVSS provenance

nvdv3.18.8HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
vendor_cisco8.8HIGH
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