cbcvebase.
CVE-2021-21983
published 2021-03-31

CVE-2021-21983: Arbitrary file write vulnerability in vRealize Operations Manager API (CVE-2021-21983) prior to 8.4 may allow an authenticated malicious actor with network…

PriorityP276medium6.5CVSS 3.1
AVNACLPRHUINSUCNIHAH
ITWEXPLOITVulnCheck KEV
Exploited in the wild
EPSS
68.56%
99.3th percentile
Arbitrary file write vulnerability in vRealize Operations Manager API (CVE-2021-21983) prior to 8.4 may allow an authenticated malicious actor with network access to the vRealize Operations Manager API can write files to arbitrary locations on the underlying photon operating system.

Affected

27 ranges· showing 25
VendorProductVersion rangeFixed in
vmwarecloud_foundation
vmwarecloud_foundation
vmwarecloud_foundation
vmwarecloud_foundation
vmwarecloud_foundation
vmwarecloud_foundation
vmwarecloud_foundation
vmwarecloud_foundation
vmwarecloud_foundation
vmwarecloud_foundation
vmwarecloud_foundation
vmwarecloud_foundation
vmwarecloud_foundation
vmwarecloud_foundation
vmwarecloud_foundation
vmwarevrealize_operations_manager
vmwarevrealize_operations_manager
vmwarevrealize_operations_manager
vmwarevrealize_operations_manager
vmwarevrealize_operations_manager
vmwarevrealize_operations_manager
vmwarevrealize_operations_manager
vmwarevrealize_operations_manager
vmwarevrealize_suite_lifecycle_manager
vmwarevrealize_suite_lifecycle_manager

Detection & IOCsextracted from sources · hover to see the quote

url/casa/private/config/slice/ha/certificate
commandPOST /casa/nodes/thumbprints HTTP/1.1 Host: {{Hostname}} Content-Type: application/json;charset=UTF-8 ["127.0.0.1:443/ui/"]
filenamecasa-security-context.xml
  • Detect exploitation of CVE-2021-21983 by monitoring POST requests to the /casa/private/config/slice/ha/certificate endpoint, which is the arbitrary file write vector requiring authentication (or chained with CVE-2021-21975 SSRF to bypass auth).
  • Detect CVE-2021-21975 SSRF exploitation (used to chain into CVE-2021-21983) by monitoring POST requests to /casa/nodes/thumbprints with internal/loopback IP addresses in the JSON body (e.g., 127.0.0.1).
  • Alert on response bodies from /casa/nodes/thumbprints containing 'vRealize Operations Manager', 'thumbprint', and 'address' simultaneously, which indicates successful SSRF exploitation leaking admin credentials.
  • The Metasploit module exploits the chain to write and execute a JSP payload on the underlying Photon OS as the 'admin' Unix user; monitor for unexpected JSP file creation and execution on vROps hosts.
  • ·Version 8.3.0 is not exploitable for credential leakage via CVE-2021-21975 and is therefore not supported by the Metasploit chained RCE module, even though it is still vulnerable to CVE-2021-21983 in isolation.
  • ·CVE-2021-21983 requires authentication on its own; the unauthenticated RCE scenario only applies when chained with the CVE-2021-21975 SSRF to steal admin credentials first.
  • ·The workaround (modifying casa-security-context.xml and restarting the CaSA service) is explicitly temporary and should not replace patching.

CVSS provenance

nvdv3.16.5MEDIUMCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:H
nvdv2.08.5HIGHAV:N/AC:L/Au:S/C:N/I:C/A:C
vulncheck6.5MEDIUM
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