criticalKEV
CVE-2021-26855
ProxyLogon: pre-auth SSRF
- Severity
- critical
- Affected product
- Microsoft Exchange OWA
- Affected versions
- Microsoft Exchange OWA all versions before the fix
- Fixed in
- Microsoft Exchange OWA vendor patch
- Detection basis
- Appliance fingerprint
- Shipped rule
- Microsoft Exchange OWA: ProxyLogon: pre-auth SSRF
- CISA KEV
- Listed as a known exploited vulnerability
- EPSS
- 97% chance of exploitation in the next 30 days
- Added to NewScan
- 2026-07-13
- Detected by
- NewScan — free, self-hosted
How NewScan reports it
APPLIANCE FINGERPRINT
NewScan fingerprints the Microsoft Exchange OWA appliance and reports this CVE when the detected version falls inside the affected range below.
References
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