CVE-2021-41567Network attack vector

Stored XSS via unfiltered subject parameter

Published Oct 8, 2021 · Updated Sep 16, 2024

Stored XSS in Tad Uploader 3.5.3 and earlier allows remote attackers to inject JavaScript through the add-subject parameter. The view-book-list function stores that parameter without filtering special characters before rendering it as page content. No authentication is required to store the payload, but a user must view the affected book list for it to execute in that user's browser context.

CVSS severity6.1
Medium
EPSS probability0.63%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Stored XSS in Tad Uploader 3.5.3 and earlier allows remote attackers to inject JavaScript through the add-subject parameter. The view-book-list function stores that parameter without filtering special characters before rendering it as page content. No authentication is required to store the payload, but a user must view the affected book list for it to execute in that user's browser context.

The record

CVE
CVE-2021-41567
Published
Oct 8, 2021
Updated
Sep 16, 2024
Vendor
Tad
Product
Tad Uploader
Classifications
CWE-79, CAPEC-592, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 8, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=0 <=3.5.3

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Tad · Tad Uploaderversion=0 <=3.5.3

Published CVSS scores

4.3NVDAV:N/AC:M/Au:N/C:N/I:P/A:N
6.1NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
6.1TWCERT/CCCVSS:3.1/AV:N/AC:L/PR:N/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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CAPEC-592Stored XSS
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo