# CVE-2021-21975: VMware Server Side Request Forgery in vRealize Operations Manager API - Exploited (CISA KEV): yes, added 2022-01-18, known ransomware use - Published: 2021-03-31 - CVSS: 9.8 CRITICAL (v3.1) - EPSS: 78.0% (100th percentile) - CWE: CWE-918 Server Side Request Forgery in vRealize Operations Manager API (CVE-2021-21975) prior to 8.4 may allow a malicious actor with network access to the vRealize Operations Manager API can perform a Server Side Request Forgery attack to steal administrative credentials. ## Edge WAF coverage (claimed by vendors, not measured) | Vendor | Status | First rule | Days after publication | |---|---|---|---| | Cloudflare | Before feed history | — | — | | AWS | No public claim | — | — | | Microsoft Azure | No public claim | — | — | | Google Cloud | Before feed history | — | — | | Fastly | Before feed history | — | — | | F5 | Before feed history | — | — | | Akamai | No public source | — | — | | OWASP CRS | Before feed history | — | — | ## Our test (measured) - OWASP Core Rule Set 4.25.0, paranoia level 1, anomaly threshold 5, default CRS settings: passed (0 of 1 requests blocked), template CVE-2021-21975, 2026-11-02 - OWASP Core Rule Set 4.25.0, paranoia level 2, anomaly threshold 5, default CRS settings: passed (0 of 1 requests blocked), template CVE-2021-21975, 2026-11-02 "No public claim" means no vendor statement names this CVE; "Before feed history" means the CVE is older than the vendor feed. In both cases generic rules may still block it. HTML: https://cve.vigilbase.com/cve/CVE-2021-21975 · JSON: https://cve.vigilbase.com/api/v1/cves/CVE-2021-21975