CVE-2021-24256Public exploitNetwork attack vector

Stored XSS via unchecked widget heading tags

Published May 5, 2021 · Updated Aug 3, 2024

Stored XSS in two Brainstorm Force Elementor Header & Footer Builder widgets before 1.5.8 allows remote authenticated users to run JavaScript. The Page Title and Site Title widgets render attacker-controlled heading_tag values as HTML element names, while a crafted size value can add a remote script source. Contributor access to the Elementor editor is required, and the script executes when the saved page is viewed or previewed.

CVSS severity5.4
Medium
EPSS probability0.59%
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 two Brainstorm Force Elementor Header & Footer Builder widgets before 1.5.8 allows remote authenticated users to run JavaScript. The Page Title and Site Title widgets render attacker-controlled heading_tag values as HTML element names, while a crafted size value can add a remote script source. Contributor access to the Elementor editor is required, and the script executes when the saved page is viewed or previewed.

The record

CVE
CVE-2021-24256
Published
May 5, 2021
Updated
Aug 3, 2024
Vendor
Brainstorm Force
Product
Elementor Header & Footer Builder
Classifications
CWE-79
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. May 5, 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=1.5.8 <1.5.8

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Brainstorm Force · Elementor Header & Footer Builderversion=1.5.8 <1.5.8

Published CVSS scores

5.4NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
6.4WordfenceCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

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

Public exploit references

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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