CVE-2021-45391Public exploitNetwork attack vector

HTTP service crash via unchecked conType copy

Published Feb 16, 2022 · Updated Aug 4, 2024

Stack buffer overflow in Tenda AX12 firmware 22.03.01.21_CN allows remote attackers to crash httpd via a crafted conType value. The sub_422CE4 handler for goform/setIPv6Status passes the unbounded conType parameter to strcpy, which copies it into a fixed-size stack buffer without validation. No authentication or user interaction is required; one crafted HTTP POST can overflow the buffer and interrupt the router's web service.

CVSS severity7.5
High
EPSS probability1.83%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stack buffer overflow in Tenda AX12 firmware 22.03.01.21_CN allows remote attackers to crash httpd via a crafted conType value. The sub_422CE4 handler for goform/setIPv6Status passes the unbounded conType parameter to strcpy, which copies it into a fixed-size stack buffer without validation. No authentication or user interaction is required; one crafted HTTP POST can overflow the buffer and interrupt the router's web service.

The record

CVE
CVE-2021-45391
Published
Feb 16, 2022
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-787, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 16, 2022CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 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

5.0NIST NVDAV:N/AC:L/Au:N/C:N/I:N/A:P
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.

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

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 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
T1499.004Application or System Exploitation

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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