CVE-2021-3704Network attack vector

Unauthenticated service interruption

Published Nov 1, 2021 · Updated Aug 3, 2024

Denial of service in HP LaserJet Pro M501 Series firmware before 20210810 allows remote attackers to interrupt printer service. HP has not published the affected firmware component, the request or protocol that reaches it, or the operation that mishandles untrusted input. Network access without authentication is sufficient, and the documented consequence is limited to reduced device availability rather than configuration changes.

CVSS severity5.3
Medium
EPSS probability1.39%
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 HP LaserJet Pro M501 Series firmware before 20210810 allows remote attackers to interrupt printer service. HP has not published the affected firmware component, the request or protocol that reaches it, or the operation that mishandles untrusted input. Network access without authentication is sufficient, and the documented consequence is limited to reduced device availability rather than configuration changes.

The record

CVE
CVE-2021-3704
Published
Nov 1, 2021
Updated
Aug 3, 2024
Vendor
HP Inc.
Product
HP LaserJet Pro M501 Series
Classifications
T1499
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Nov 1, 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?

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

  1. Affected versionversion=before 20210810

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

HP Inc. · HP LaserJet Pro M501 Seriesversion=before 20210810

Published CVSS scores

5.3HP Inc.CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
7.8NIST NVDAV:N/AC:L/Au:N/C:N/I:N/A:C

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 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 exploitUnconfirmed

Weakness, pattern, technique

T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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