cbcvebase.
CVE-2021-21980
published 2021-11-24

CVE-2021-21980: The vSphere Web Client (FLEX/Flash) contains an unauthorized arbitrary file read vulnerability. A malicious actor with network access to port 443 on vCenter…

PriorityP277high7.5CVSS 3.1
AVNACLPRNUINSUCHINAN
ITWEXPLOITVulnCheck KEV
Exploited in the wild
EPSS
4.60%
90.6th percentile
The vSphere Web Client (FLEX/Flash) contains an unauthorized arbitrary file read vulnerability. A malicious actor with network access to port 443 on vCenter Server may exploit this issue to gain access to sensitive information.

Affected

3 ranges
VendorProductVersion rangeFixed in
vmwarecloud_foundation
vmwarevcenter_server
vmwarevcenter_server

Detection & IOCsextracted from sources · hover to see the quote

  • Monitor for unauthorized file read attempts targeting port 443 on vCenter Server via the vSphere Web Client (FLEX/Flash) endpoint
  • Alert on inbound connections to TCP/443 on vCenter Server originating from untrusted/external network sources targeting the FLEX/Flash Web Client component
  • ·Affected products include VMware vCenter Server, VMware Cloud Foundation, and vSphere; scope patching and detection accordingly
  • ·This vulnerability is in the legacy FLEX/Flash-based vSphere Web Client; environments that have already migrated away from Flash/FLEX may have reduced exposure, but patching is still required

CVSS provenance

nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
nvdv2.05.0MEDIUMAV:N/AC:L/Au:N/C:P/I:N/A:N
vulncheck7.5HIGH
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