CVE-2021-26858
Is CVE-2021-26858 real, exploitable, or a false positive? Here's the community verdict.
signals
public sources
Confirmed exploited in the wild. Patch this first, regardless of the base score.
baseline read
auto · not a community verdict
Real — exploited in the wild
CISA confirms active exploitation. Treat scanner hits as true positives unless your specific version or config is unaffected.
Based on CISA KEV
Confirm or dispute →CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Microsoft Exchange Server Remote Code Execution Vulnerability
NVD only has a brief summary for this one. The community fills in the real-world detail below.
References
Published
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Community ground truth
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In your experience, is this finding real and exploitable?
awaiting field verdictsCurated baseline: TruePositive's read from public sources is Real & exploitable — a starting point, not a community verdict.
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Field notes & remediation
Verdicts are the quick signal. Notes are the evidence and fixes behind them.
- 0
Microsoft Exchange Server Remote Code Execution Vulnerability — Microsoft Exchange Server contains an unspecified vulnerability that allows for remote code execution. This vulnerability is part of the ProxyLogon exploit chain. Listed in the CISA KEV catalog (added 2021-11-03) — confirmed exploited in the wild, not theoretical. It is linked to known ransomware campaigns. FIRST EPSS puts the chance of exploitation in the next 30 days at ~90%. Treat it as real and prioritize remediation over triage.
- 0
Required action for Microsoft Exchange Server: Apply updates per vendor instructions. CISA set a federal remediation due date of 2022-05-03. After patching, verify the vulnerable path is no longer reachable before closing the finding.