CVE-2021-33822

7.5 highEPSS 1.9%

High (7.5) in sing4g 4gee router hh70vb firmware. EPSS 1.9% chance of exploitation in the next 30 days.

An issue was discovered on 4GEE ROUTER HH70VB Version HH70_E1_02.00_22. Attackers can use slowhttptest tool to send incomplete HTTP request, which could make server keep waiting for the packet to finish the connection, until its resource exhausted. Then the web server is denial-of-service.

Severity

CVSS 3.1

7.5 high

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

EPSS: 1.9% chance of exploitation in the next 30 days; higher than 80% of CVEs (scores of 2026-10-31)
CWE: CWE-400
Published: 2021-06-18
Modified: 2026-06-17
Record from: the NVD, synced 2026-10-19

Affected

sing4g:4gee_router_hh70vb_firmware

References

https://github.com/Jian-Xian/CVE-POC/blob/master/CVE-2021-33822.md
https://github.com/shekyan/slowhttptest
https://www.sing4g.com/product-page/4gee-router-hh70vb-4g-300mbps-2lan-32wifi
https://github.com/Jian-Xian/CVE-POC/blob/master/CVE-2021-33822.md
https://github.com/shekyan/slowhttptest

Check your stack JSON