TI-2021-06202 Aliases CVE-2021-23838 GHSA-w58h-cm85-98cc

An issue was discovered in flatCore before 2.0.0 build 139.

LOW 24CWE-79Published 2021-01-15 · Updated 2024-08-03

Key facts

Attack vector: Network
Privileges required: High
User interaction: Required
Attack complexity: Low
Impact type: Cross-site scripting
Confidentiality · integrity · availability: Low · Low · None
Fix status: No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-79.

Summary

An issue was discovered in flatCore before 2.0.0 build 139. A reflected XSS vulnerability was identified in the media_filter HTTP request body parameter for the acp interface. The affected parameter accepts malicious client-side script without proper input sanitization. For example, a malicious user can leverage this vulnerability to steal cookies from a victim user and perform a session-hijacking attack, which may then lead to unauthorized access to the site.

Why it matters now

EPSS 0.00993 62nd percentileScored 2026-11-07

Public exploit Yes 1 exploit referenceTagged by NVD

Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
—	—	all versions	—	No fix listed	CNA

— Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:a:flatcore:flatcore::::::::	up to 2.0.0	Vulnerable	flatcore

cpe:2.3:a:flatcore:flatcore:*:*:*:*:*:*:*:* Versions up to 2.0.0 Vulnerable ·flatcore

Remediation

No fixed version listed by the sources yet.

Timeline

2026-10-02 Threatist record created from CVE-2021-23838
2026-10-03 Alias added: GHSA-w58h-cm85-98cc

References

Exploit 1

http://packetstormsecurity.com/files/160936/flatCore-CMS-XSS-File-Disclosure-SQL-Injection.html

Advisory 2

TI-2021-17581 Cross site scripting (XSS) vulnerability in flatCore-CMS 2.2.15 allows attackers to… CVSS 3.1MEDIUM 5.4
TI-2019-10413 A CSRF vulnerability was found in flatCore before 1.5, leading to the upload of arbitrary… CVSS 3.0HIGH 8.8
TI-2019-07947 An issue was discovered in flatCore 1.4.7. CVSS 3.0HIGH 7.2
TI-2020-13217 flatCore before 1.5.7 allows upload and execution of a .php file by an admin. CVSS 3.1HIGH 7.2
TI-2021-06201 An issue was discovered in flatCore before 2.0.0 build 139. CVSS 3.1MEDIUM 6.5
TI-2017-06862 Cross site scripting (XSS) vulnerability in pages.edit_form.php in flatCore 1.4.6 allows… CVSS 3.0MEDIUM 6.1

See all 9 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences