CVE-2021-24686Public exploitNetwork attack vector

Stored script execution via unescaped CSS class

Published Feb 1, 2022 · Updated Aug 3, 2024

Stored XSS in SVG Support before 2.3.20 allows remote authenticated users to execute script via a crafted CSS class setting. The Advanced Mode “CSS Class to target” value is written into an HTML attribute without output escaping, so injected markup persists. High-privilege access and Advanced Mode are required, and a victim must load the affected output for the stored script to run in the victim's browser.

CVSS severity4.8
Medium
EPSS probability0.65%
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 SVG Support before 2.3.20 allows remote authenticated users to execute script via a crafted CSS class setting. The Advanced Mode “CSS Class to target” value is written into an HTML attribute without output escaping, so injected markup persists. High-privilege access and Advanced Mode are required, and a victim must load the affected output for the stored script to run in the victim's browser.

The record

CVE
CVE-2021-24686
Published
Feb 1, 2022
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-79, T1059.007
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Feb 1, 2022CVE 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 vectornetwork
Required privilegesadmin

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

3.5NIST NVDAV:N/AC:M/Au:S/C:N/I:P/A:N
4.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:H/UI:R/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
Privilegesadmin
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1059.007JavaScript/JScript

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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