CVE-2021-1374Network attack vector

Stored XSS via unvalidated configuration field

Published Mar 24, 2021 · Updated Nov 8, 2024

Stored XSS in Cisco IOS XE Wireless Controller software allows remote authenticated users to execute scripts in another user's browser. The web interface insufficiently validates malicious code placed in a configuration field, stores it, and renders it when another user opens the crafted item. Exploitation requires high-privileged device access and persuading another user to click the item, exposing interface data or actions in that user's browser context.

CVSS severity4.8
Medium
EPSS probability0.64%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stored XSS in Cisco IOS XE Wireless Controller software allows remote authenticated users to execute scripts in another user's browser. The web interface insufficiently validates malicious code placed in a configuration field, stores it, and renders it when another user opens the crafted item. Exploitation requires high-privileged device access and persuading another user to click the item, exposing interface data or actions in that user's browser context.

The record

CVE
CVE-2021-1374
Published
Mar 24, 2021
Updated
Nov 8, 2024
Vendor
ClamAV
Product
Cisco IOS XE Software
Classifications
CWE-79, T1204.001
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Mar 24, 2021CVE publishedPublication date reported by the CVE source.
  2. Nov 8, 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 privilegesadmin

What is affected?

ClamAV · Cisco IOS XE Softwareversion=n/a

Published CVSS scores

4.8CiscoCVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N/E:X/RL:X/RC:X

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
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1204.001Malicious 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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