CVE-2021-28481
Exploitation likely. EPSS gives it a 36% chance of exploitation in the next 30 days. A vendor fix is available.
What to do
The vendor has published a fix. Version details are below where the sources state them.
What it is
From the CVE record
Microsoft Exchange Server Remote Code Execution Vulnerability
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Not in the catalog. CISA has not confirmed exploitation.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
36% chance of exploitation activity in the next 30 days, which ranks it in the 98th percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
6 events over 1899 days, from the signal feeds we watch.
- OpenVAS check added
- Nuclei check added
- Patch availablerecord updated
- Publishedweakness classified
Affected products
- Microsoft Exchange ServerOperating Systems
- Microsoft Exchange Server 2019 Cumulative Update 9Enterprise Software / itsm-monitoring
- Microsoft Exchange Server 2016 Cumulative Update 20Enterprise Software / itsm-monitoring
- Microsoft Exchange Server 2013 Cumulative Update 23Enterprise Software / itsm-monitoring
- Microsoft Exchange Server 2016 Cumulative Update 19Enterprise Software / itsm-monitoring
- Microsoft Exchange Server 2019 Cumulative Update 8Enterprise Software / itsm-monitoring
- exchange serverOperating Systems / windows
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Scored 9.8 by NVD.
How it is reached
- Attack Vector NetworkExploitable remotely over the network without any special conditions
- Attack Complexity LowNo special conditions — the attack can be reliably reproduced
- Privileges Required NoneNo authentication required — anyone can exploit this
- User Interaction NoneNo user interaction needed — fully automated exploitation
Scope
- Scope UnchangedImpact is limited to the vulnerable component itself
Impact if exploited
- Confidentiality HighTotal information disclosure — all data in the component is compromised
- Integrity HighTotal loss of integrity — attacker can modify any data in the component
- Availability HighTotal denial of service — the component is completely unavailable
Weaknesses
Sources
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