CVE-2021-4267Network attack vector

Browser script execution via unescaped discussion title

Published Dec 21, 2022 · Updated Apr 14, 2025

Stored cross-site scripting in Tad Discuss before 2021-03-23 allows remote authenticated users to execute script through DiscussTitle. The discuss.php, function.php, and index.php rendering paths emit stored DiscussTitle values into HTML and notification templates without contextual encoding. A second user must view the crafted title; injected script then runs in the affected site's browser origin and can read or change data available to that page.

CVSS severity6.1
Medium
EPSS probability0.47%
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 Tad Discuss before 2021-03-23 allows remote authenticated users to execute script through DiscussTitle. The discuss.php, function.php, and index.php rendering paths emit stored DiscussTitle values into HTML and notification templates without contextual encoding. A second user must view the crafted title; injected script then runs in the affected site's browser origin and can read or change data available to that page.

The record

CVE
CVE-2021-4267
Published
Dec 21, 2022
Updated
Apr 14, 2025
Vendor
Tad
Product
Tad Discuss
Classifications
CWE-79, CWE-707, T1059.007
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Dec 21, 2022CVE publishedPublication date reported by the CVE source.
  2. Apr 14, 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?

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

  1. Affected versionversion=n/a

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Tad · Tad Discussversion=n/a

Published CVSS scores

6.1NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
3.5VulDBCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/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 exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CWE-707Improper Neutralization
T1059.007JavaScript/JScript

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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