CVE-2021-20679

Device halt via crafted network command

Published Mar 25, 2021 · Updated Aug 3, 2024

Denial of service in affected Fuji Xerox multifunction devices and printers allows remote attackers to stop a device via a crafted command. The device accepts a specially crafted network command and enters system fault 116-324, terminating normal operation; the affected parser and validation error are undisclosed. Unauthenticated network access is sufficient, and recovery requires cycling the physical power button; stored information is unaffected.

CVSS severity4.3
Medium
EPSS probability1.55%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Denial of service in affected Fuji Xerox multifunction devices and printers allows remote attackers to stop a device via a crafted command. The device accepts a specially crafted network command and enters system fault 116-324, terminating normal operation; the affected parser and validation error are undisclosed. Unauthenticated network access is sufficient, and recovery requires cycling the physical power button; stored information is unaffected.

The record

CVE
CVE-2021-20679
Published
Mar 25, 2021
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
T1499.004
Attack vector
adjacent
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 25, 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

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
3.3JPCERT/CCAV:A/AC:L/Au:N/C:N/I:N/A:P
7.8NIST NVDAV:N/AC:L/Au:N/C:N/I:N/A:C
4.3JPCERT/CCCVSS:3.0/AV:A/AC:L/PR:N/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.

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)
Vectoradjacent
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499.004Application or System Exploitation

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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