CVE-2021-36573Public exploitNetwork attack vector

Stored XSS via unescaped uploaded image filename

Published Dec 15, 2022 · Updated Apr 21, 2025

Stored XSS in Feehi CMS 2.1.1 and earlier allows remote authenticated users to execute scripts via a crafted image filename. The article-update text editor accepts quote and angle-bracket characters in an image filename, then emits that name into page output without neutralization. Article-editing access and subsequent page rendering are required; the injected script runs in the viewing user's browser context.

CVSS severity5.4
Medium
EPSS probability0.46%
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 Feehi CMS 2.1.1 and earlier allows remote authenticated users to execute scripts via a crafted image filename. The article-update text editor accepts quote and angle-bracket characters in an image filename, then emits that name into page output without neutralization. Article-editing access and subsequent page rendering are required; the injected script runs in the viewing user's browser context.

The record

CVE
CVE-2021-36573
Published
Dec 15, 2022
Updated
Apr 21, 2025
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-79, CWE-434, T1203
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Dec 15, 2022CVE publishedPublication date reported by the CVE source.
  2. Apr 21, 2025Record 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 privilegesauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

5.4GitHub Advisory DatabaseCVSS:3.1/AV:N/AC:L/PR:L/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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 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')
CWE-434Unrestricted Upload of File with Dangerous Type
T1203Exploitation for Client Execution

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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