CVE-2021-1571Network attack vector

HTML injection via unchecked page parameters

Published Jun 16, 2021 · Updated Nov 7, 2024

HTML injection in Cisco 220 Series Smart Plus Switches before 1.2.0.6 allows remote attackers to alter management pages via crafted links. Affected management pages accept HTML code in parameter values without proper checks and incorporate it into page content. The web interface must be enabled and a user must follow the link; the injected markup can redirect that user to a malicious website.

CVSS severity6.1
Medium
EPSS probability9.72%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

HTML injection in Cisco 220 Series Smart Plus Switches before 1.2.0.6 allows remote attackers to alter management pages via crafted links. Affected management pages accept HTML code in parameter values without proper checks and incorporate it into page content. The web interface must be enabled and a user must follow the link; the injected markup can redirect that user to a malicious website.

The record

CVE
CVE-2021-1571
Published
Jun 16, 2021
Updated
Nov 7, 2024
Vendor
ClamAV
Product
Cisco 220 Series Smart Plus Switches
Classifications
CWE-287, CWE-79, T1204.001
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 16, 2021CVE publishedPublication date reported by the CVE source.
  2. Nov 7, 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=n/a

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

ClamAV · Cisco 220 Series Smart Plus Switchesversion=n/a

Published CVSS scores

6.1NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
6.1Cisco Security AdvisoryCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
4.3NVDAV:N/AC:M/Au:N/C:N/I:P/A:N
7.2Cisco CNACVSS:3.1/AV:N/AC:L/PR:H/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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-287Improper Authentication
CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1204.001User Execution: Malicious Link

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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