How severe is CVE-2021-31249?

CVE-2021-31249 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2021-31249 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 18% (97th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-31249?

CVE-2021-31249 primarily affects Chiyu-tech Bf-430 Firmware. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-31249?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-31249 published?

CVE-2021-31249 was published on 2021-06-04 and last updated on 2026-06-17.

CVE-2021-31249

CVE-2021-31249 is a medium-severity vulnerability in Chiyu-tech Bf-430 Firmware with a CVSS 3.x base score of 6.5. Its EPSS exploit-prediction score of 18% places it in the 97th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-74.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 6.4
EPSS exploit prediction: 18% (97th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-74
Affected product: Chiyu-tech Bf-430 Firmware
Published: 2021-06-04
Last modified: 2026-06-17

Description

A CRLF injection vulnerability was found on BF-430, BF-431, and BF-450M TCP/IP Converter devices from CHIYU Technology Inc due to a lack of validation on the parameter redirect= available on multiple CGI components.

Frequently asked questions

What is CVE-2021-31249?: A CRLF injection vulnerability was found on BF-430, BF-431, and BF-450M TCP/IP Converter devices from CHIYU Technology Inc due to a lack of validation on the parameter redirect= available on multiple CGI components.
How severe is CVE-2021-31249?: CVE-2021-31249 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2021-31249 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 18% (97th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-31249?: CVE-2021-31249 primarily affects Chiyu-tech Bf-430 Firmware. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-31249?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-31249 published?: CVE-2021-31249 was published on 2021-06-04 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:o:chiyu-tech:bf-430_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:chiyu-tech:bf-431_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:chiyu-tech:bf-450m_firmware:-:*:*:*:*:*:*:*

More vulnerabilities in Chiyu-tech Bf-430 Firmware

CVE-2021-31251 — Critical (CVSS 9.8): An authentication bypass in telnet server in BF-430 and BF431 232/422 TCP/IP Converter, BF-450M and SEMAC from CHIYU…
CVE-2021-31252 — Medium (CVSS 6.1): An open redirect vulnerability exists in BF-630, BF-450M, BF-430, BF-431, BF631-W, BF830-W, Webpass, and SEMAC devices…
CVE-2021-31641 — Medium (CVSS 6.1): An unauthenticated XSS vulnerability exists in several IoT devices from CHIYU Technology, including BF-630, BF-450M,…
CVE-2021-31250 — Medium (CVSS 5.4): Multiple storage XSS vulnerabilities were discovered on BF-430, BF-431 and BF-450M TCP/IP Converter devices from CHIYU…

All CVEs affecting Chiyu-tech Bf-430 Firmware →

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