Known exploited vulnerability
CVE-2021-21973
The short answer
CVE-2021-21973 affects n/a VMware vCenter Server and is rated medium (CVSS 5.3). CISA added it to the Known Exploited Vulnerabilities catalog on 2022-03-07: attackers are using it, so patch it first.
What it is
The vSphere Client (HTML5) contains an SSRF (Server Side Request Forgery) vulnerability due to improper validation of URLs in a vCenter Server plugin. A malicious actor with network access to port 443 may exploit this issue by sending a POST request to vCenter Server plugin leading to information disclosure. This affects: VMware vCenter Server (7.x before 7.0 U1c, 6.7 before 6.7 U3l and 6.5 before 6.5 U3n) and VMware Cloud Foundation (4.x before 4.2 and 3.x before 3.10.1.2).
Weakness: CWE-918.
Severity
5.3 medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Exploited (CISA KEV)
Yes, since Mar 7, 2022
Federal due date Mar 21, 2022
EPSS, next 30 days
88%
Higher than 100% of scored CVEs
How it can be exploited
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- Low
- Integrity impact
- None
- Availability impact
- None
What CISA says to do
Apply updates per vendor instructions.
Affected products
VMware vCenter Server, VMware Cloud Foundation. NVD's record lists the exact affected versions.
References
- www.vmware.com/security/advisories/VMSA-2021-0002.html Vendor Advisory
- www.vmware.com/security/advisories/VMSA-2021-0002.html Vendor Advisory
- www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-21973 US Government Resource
Questions
Is CVE-2021-21973 being exploited?
Yes. CISA added CVE-2021-21973 to its Known Exploited Vulnerabilities catalog on 2022-03-07, with a federal remediation due date of 2022-03-21.
How do I fix CVE-2021-21973?
CISA's required action: Apply updates per vendor instructions.
From NVD, CISA KEV, FIRST EPSS and OSV.dev, checked . Status on NVD: Analyzed. The description is NVD's text, quoted as published.
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