What is the CVSS score of CVE-2021-31250?

CVE-2021-31250 has a CVSS 3.1 base score of 5.4 (Medium). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N. EPSS exploitation probability: 79.6%.

Is there a public PoC exploit available for CVE-2021-31250?

Yes, a public proof-of-concept exploit is available for CVE-2021-31250. Prioritise patching immediately. EPSS: 79.6%.

Bf 430 Firmware CVE-2021-31250

MEDIUM

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

2021-06-04 cve@mitre.org

XSS Bf 430 Firmware Bf 431 Firmware Bf 450M Firmware

5.4

CVSS 3.1 · NVD

Severity by source

NVD PRIMARY

5.4 MEDIUM

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

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

Required

Scope

Changed

Confidentiality

Low

Integrity

Low

Availability

None

Lifecycle Timeline

CVE Published

Jun 04, 2021 - 21:15 nvd

MEDIUM 5.4

DescriptionNVD

AnalysisAI

Multiple storage XSS vulnerabilities were discovered on BF-430, BF-431 and BF-450M TCP/IP Converter devices from CHIYU Technology Inc due to a lack of sanitization of the input on the components. Rated medium severity (CVSS 5.4), 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. Multiple storage XSS vulnerabilities were discovered on BF-430, BF-431 and BF-450M TCP/IP Converter devices from CHIYU Technology Inc due to a lack of sanitization of the input on the components man.cgi, if.cgi, dhcpc.cgi, ppp.cgi. Affected products include: Chiyu-Tech Bf-430 Firmware, Chiyu-Tech Bf-431 Firmware, Chiyu-Tech Bf-450M Firmware.

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.