CVE-2022-40075Public exploitNetwork attack vector

Service interruption via unchecked web input

Published Sep 19, 2022 · Updated Aug 3, 2024

Buffer overflow in Tenda AC21 16.03.08.15 allows remote attackers to restart the httpd service via a crafted web request. The form_fast_setting_wifi_set handler in /bin/httpd processes input without checking its length, causing an out-of-bounds write. No authentication or user interaction is required; successful exploitation interrupts router management by restarting httpd.

CVSS severity7.5
High
EPSS probability0.99%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Buffer overflow in Tenda AC21 16.03.08.15 allows remote attackers to restart the httpd service via a crafted web request. The form_fast_setting_wifi_set handler in /bin/httpd processes input without checking its length, causing an out-of-bounds write. No authentication or user interaction is required; successful exploitation interrupts router management by restarting httpd.

The record

CVE
CVE-2022-40075
Published
Sep 19, 2022
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-787, T1499
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 19, 2022CVE 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

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.

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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-787Out-of-bounds Write
T1499Endpoint Denial of Service

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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