CVE-2021-27573Public exploitNetwork attack vector

Unauthenticated code execution via unchecked UDP keystrokes

Published May 7, 2021 · Updated Aug 3, 2024

Missing authorization in Emote Remote Mouse 4.0.0.0 and earlier allows remote attackers to execute arbitrary code through crafted UDP packets. The UDP listener in RemoteMouseCore.exe passes unauthenticated key messages to an input-simulation routine that injects arbitrary keystrokes. Network access to UDP port 1978 is sufficient; injected Windows Run and PowerShell keystrokes execute commands in the server user's context.

CVSS severity9.8
Critical
EPSS probability3.64%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Missing authorization in Emote Remote Mouse 4.0.0.0 and earlier allows remote attackers to execute arbitrary code through crafted UDP packets. The UDP listener in RemoteMouseCore.exe passes unauthenticated key messages to an input-simulation routine that injects arbitrary keystrokes. Network access to UDP port 1978 is sufficient; injected Windows Run and PowerShell keystrokes execute commands in the server user's context.

The record

CVE
CVE-2021-27573
Published
May 7, 2021
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-862, T1059.001
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 7, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

7.5NIST NVDAV:N/AC:L/Au:N/C:P/I:P/A:P
9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-862Missing Authorization
T1059.001PowerShell

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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