CVE-2021-33822Public exploitNetwork attack vector

Unauthenticated web server outage via incomplete HTTP requests

Published Jun 18, 2021 · Updated Aug 3, 2024

Denial of service in 4GEE ROUTER HH70VB HH70_E1_02.00_22 allows remote attackers to interrupt the web server via incomplete HTTP requests. The HTTP server retains each unfinished connection while awaiting request completion, exhausting its finite connection resources. No authentication or user interaction is required; sustained network access can make only the router's web interface unavailable.

CVSS severity7.5
High
EPSS probability1.93%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Denial of service in 4GEE ROUTER HH70VB HH70_E1_02.00_22 allows remote attackers to interrupt the web server via incomplete HTTP requests. The HTTP server retains each unfinished connection while awaiting request completion, exhausting its finite connection resources. No authentication or user interaction is required; sustained network access can make only the router's web interface unavailable.

The record

CVE
CVE-2021-33822
Published
Jun 18, 2021
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-400, T1499.003
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 18, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
5.0NIST NVDAV:N/AC:L/Au:N/C:N/I:N/A:P

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-400Uncontrolled Resource Consumption
T1499.003Application Exhaustion Flood

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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