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.
CVE-2021-31249
Score 6.5 from GitHub Security Advisory published 2022-05-24. NVD baseline CVSS 6.5; sources differ by 0.0.
- Lower severity and no public exploit yet
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 6.5
- EG Score
- 6.5(medium)
- EG Risk
- 50(Track)EG Risk 50/100SSVC: Track
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity65% × 45%Exploitation40% × 40%Automatability30% × 15%Action: Routine — remediate on your standard cadence. - EPSS
- 96.9%
- KEV
- Not listed
Published
June 4, 2021
Last Modified
November 21, 2024
References (6)
- cve@mitrehttps://gitbook.seguranca-informatica.pt/cve-and-exploits/cves/chiyu-iot-devices#cve-2021-31249
- cve@mitrehttps://seguranca-informatica.pt/dancing-in-the-iot-chiyu-devices-vulnerable-to-remote-attacks/
- cve@mitrehttps://www.chiyu-tech.com/msg/message-Firmware-update-87.html
- af854a3a-2127-422b-91ae-364da2661108https://gitbook.seguranca-informatica.pt/cve-and-exploits/cves/chiyu-iot-devices#cve-2021-31249
- af854a3a-2127-422b-91ae-364da2661108https://seguranca-informatica.pt/dancing-in-the-iot-chiyu-devices-vulnerable-to-remote-attacks/
- af854a3a-2127-422b-91ae-364da2661108https://www.chiyu-tech.com/msg/message-Firmware-update-87.html
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 13× in last 7d / 45× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-07-23 14:16 UTCEPSS rescore
- 2026-07-23 02:00 UTCEG score recompute
- 2026-07-22 22:47 UTCEG score recompute▼ 2.50
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- 2026-05-29 13:42 UTCEPSS rescore
- 2026-05-26 15:27 UTCEG score recompute
- 2026-05-26 15:27 UTCGHSA enrichment
Publicly available exploits
(1 reference)Working exploit code is in the public domain. Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.
- Nucleihttp/cves/2021/CVE-2021-31249.yamlFirst seen Jan 1, 2021
CHIYU TCP/IP Converter - Carriage Return Line Feed Injection
Open source ↗
Frequently asked(5)
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Dependency Blast Radius
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