cbcvebase.
CVE-2020-3243
published 2020-04-15

CVE-2020-3243: Multiple vulnerabilities in the REST API of Cisco UCS Director and Cisco UCS Director Express for Big Data may allow a remote attacker to bypass authentication…

PriorityP185critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EXPLOIT
EPSS
88.37%
99.8th percentile
Multiple vulnerabilities in the REST API of Cisco UCS Director and Cisco UCS Director Express for Big Data may allow a remote attacker to bypass authentication or conduct directory traversal attacks on an affected device. For more information about these vulnerabilities, see the Details section of this advisory.

Affected

21 ranges
VendorProductVersion rangeFixed in
ciscocisco_ucs_director
ciscoucs_director
ciscoucs_director
ciscoucs_director
ciscoucs_director
ciscoucs_director
ciscoucs_director
ciscoucs_director
ciscoucs_director
ciscoucs_director
ciscoucs_director
ciscoucs_director
ciscoucs_director
ciscoucs_director
ciscoucs_director
ciscoucs_director
ciscoucs_director
ciscoucs_director
ciscoucs_director
ciscoucs_director_and_cisco_ucs_director_express_for_big_data
ciscoucs_director_express_for_big_data<= 3.7.3.0

Detection & IOCsextracted from sources · hover to see the quote

url/app/api/rest
  • Monitor REST API endpoints on Cisco UCS Director for unauthenticated or anomalous requests that include directory traversal sequences (e.g., '../') in path parameters, which may indicate exploitation of CVE-2020-3243.
  • Alert on REST API requests that successfully retrieve or leak the administrator's API key without prior authenticated session establishment, as this is the primary authentication bypass primitive used in exploitation.
  • Flag use of the LEAK_FILE option pattern: requests attempting to read arbitrary absolute paths via the REST API directory traversal, which can be used to exfiltrate sensitive files beyond just the API key.
  • ·Exploitation has been confirmed on Cisco UCS Director versions below 6.7.4.0; the VMware distribution of 6.7.3.0 was specifically tested. Ensure version checks in detections account for this range.
  • ·If an attacker already possesses a valid API key, the authentication bypass step is unnecessary. Detections should not rely solely on observing the bypass phase; monitor for suspicious Cloupia script execution regardless of how the API key was obtained.

CVSS provenance

nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
nvdv3.09.8CRITICALCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
nvdv2.07.5HIGHAV:N/AC:L/Au:N/C:P/I:P/A:P
vendor_cisco9.8CRITICAL
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