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Fencer Vulns
medium 6.5

CVE-2021-31249 json

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…

published 2021-06-04 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-18161

cvss
6.5
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
18.0%
EPSS 18.0% chance of exploitation in 30 days, percentile 97%
public exploits
0
none known, plus a Nuclei check

Summary

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.

Exploit prediction

18.00% chance of exploitation in the next 30 days, higher than 97% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • Nuclei template CHIYU TCP/IP Converter - Carriage Return Line Feed Injection nuclei detection template
  • seguranca-informatica.pt https://seguranca-informatica.pt/dancing-in-the-iot-chiyu-devices-vulnerable-to-remote-attacks/ referenced PoC, tagged "exploit" by a source, unverified
  • gitbook.seguranca-informatica.pt https://gitbook.seguranca-informatica.pt/cve-and-exploits/cves/chiyu-iot-devices#cve-2021-31249 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
NVD 3.1 6.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
NVD 2.0 6.4 AV:N/AC:L/Au:N/C:P/I:P/A:N

Classification

Weakness
  • CWE-74 Improper Neutralization of Special Elements in Output Used by a Downstream Component

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.