What is the CVSS score of CVE-2021-23838?

CVE-2021-23838 has a CVSS 3.1 base score of 4.8 (Medium). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N. EPSS exploitation probability: 1.0%.

Is there a public PoC exploit available for CVE-2021-23838?

Yes, a public proof-of-concept exploit is available for CVE-2021-23838. Prioritise patching immediately. EPSS: 1.0%.

Flatcore CVE-2021-23838

MEDIUM

Cross-site Scripting (XSS) (CWE-79)

2021-01-15 cve@mitre.org

XSS Authentication Bypass Flatcore

4.8

CVSS 3.1 · NVD

Severity by source

NVD PRIMARY

4.8 MEDIUM

AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N

Attack Vector

Network

Attack Complexity

Low

Privileges Required

High

User Interaction

Required

Scope

Changed

Confidentiality

Low

Integrity

Low

Availability

None

Lifecycle Timeline

CVE Published

Jan 15, 2021 - 07:15 nvd

MEDIUM 4.8

DescriptionNVD

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.

AnalysisAI

An issue was discovered in flatCore before 2.0.0 build 139. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.

Technical ContextAI

This vulnerability is classified as Cross-Site Scripting (XSS) (CWE-79), which allows attackers to inject malicious scripts into web pages viewed by other users. 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. Affected products include: Flatcore. Version information: before 2.0.0.

RemediationAI

No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Sanitize all user input, use Content-Security-Policy headers, encode output contextually (HTML, JS, URL). Use frameworks with built-in XSS protection.