CVE-2021-24737Public exploitNetwork attack vector

Stored XSS via unescaped Follow and Unfollow messages

Published Oct 11, 2021 · Updated Aug 3, 2024

Stored XSS in wpDiscuz 7.3.0 and earlier allows remote authenticated users to execute script through Follow and Unfollow message settings. The Phrases panel stores those administrator-supplied messages without proper sanitization or output escaping, and the Follow or Unfollow action inserts them into the page. Administrator access is required to save a payload, and script runs in the affected site's origin when another user activates the corresponding control.

CVSS severity4.8
Medium
EPSS probability0.62%
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 wpDiscuz 7.3.0 and earlier allows remote authenticated users to execute script through Follow and Unfollow message settings. The Phrases panel stores those administrator-supplied messages without proper sanitization or output escaping, and the Follow or Unfollow action inserts them into the page. Administrator access is required to save a payload, and script runs in the affected site's origin when another user activates the corresponding control.

The record

CVE
CVE-2021-24737
Published
Oct 11, 2021
Updated
Aug 3, 2024
Vendor
gVectors
Product
wpDiscuz
Classifications
CWE-79, T1203
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Oct 11, 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=7.3.0 <=7.3.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

gVectors · wpDiscuzversion=7.3.0 <=7.3.0

Published CVSS scores

3.5NISTAV:N/AC:M/Au:S/C:N/I:P/A:N
4.8NISTCVSS: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')
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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