CVE-2021-24897Public exploitNetwork attack vector

Contributor-level stored XSS via unescaped subtitle output

Published Mar 14, 2022 · Updated Aug 3, 2024

Stored cross-site scripting in ViitorCloud Add Subtitle 1.1.0 and earlier allows remote authenticated users to execute script via a subtitle. The plugin emits the classic editor's stored sub-title field in page output without sanitizing the value or escaping it for HTML. Contributor-level access is sufficient to save a payload, but execution requires another user to view or preview the affected post.

CVSS severity5.4
Medium
EPSS probability0.60%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stored cross-site scripting in ViitorCloud Add Subtitle 1.1.0 and earlier allows remote authenticated users to execute script via a subtitle. The plugin emits the classic editor's stored sub-title field in page output without sanitizing the value or escaping it for HTML. Contributor-level access is sufficient to save a payload, but execution requires another user to view or preview the affected post.

The record

CVE
CVE-2021-24897
Published
Mar 14, 2022
Updated
Aug 3, 2024
Vendor
ViitorCloud Technologies Pvt Ltd
Product
Add Subtitle
Classifications
CWE-79, T1059.007
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Mar 14, 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?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=1.1.0 <=1.1.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

ViitorCloud Technologies Pvt Ltd · Add Subtitleversion=1.1.0 <=1.1.0

Published CVSS scores

5.4NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
3.5NIST NVDAV:N/AC:M/Au:S/C:N/I:P/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')
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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