CVE-2021-45916

Partial service disruption via unchecked agent response

Published Jan 3, 2022 · Updated Sep 16, 2024

Improper input validation in Shockwall before 7.20.0401 allows remote authenticated users on the local network to disrupt server services. A specific server-side programming function accepts message content returned by an endpoint agent without validating it before processing. Exploitation requires ordinary-user authentication and local-network access, and the reported consequence is limited to abnormal operation of part of the server service.

CVSS severity3.5
Low
EPSS probability0.30%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper input validation in Shockwall before 7.20.0401 allows remote authenticated users on the local network to disrupt server services. A specific server-side programming function accepts message content returned by an endpoint agent without validating it before processing. Exploitation requires ordinary-user authentication and local-network access, and the reported consequence is limited to abnormal operation of part of the server service.

The record

CVE
CVE-2021-45916
Published
Jan 3, 2022
Updated
Sep 16, 2024
Vendor
Sun & Moon Rise Co., Ltd.
Product
Shockwall
Classifications
CWE-20, T1499
Attack vector
adjacent
Privileges
authenticated

Timeline

How it unfolded

  1. Jan 3, 2022CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=unspecified <7.20.0401

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesauthenticated

What is affected?

Sun & Moon Rise Co., Ltd. · Shockwallversion=unspecified <7.20.0401

Published CVSS scores

3.5TWCERT/CCCVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

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.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectoradjacent
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-20Improper Input Validation
T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

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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