CVE-2023-40895Network attack vector

Unauthenticated router crash via overlong list parameter

Published Aug 24, 2023 · Updated Oct 3, 2024

Stack-based buffer overflow in Tenda AC8 v4.0 firmware si_V16.03.34.06_cn allows remote attackers to crash the router via HTTP. Published material identifies the list parameter at /goform/SetVirtualServerCfg but does not disclose the exact unsafe copy operation. The endpoint requires no authentication, and device testing records a real crash rather than demonstrated code execution.

CVSS severity9.8
Critical
EPSS probability0.93%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stack-based buffer overflow in Tenda AC8 v4.0 firmware si_V16.03.34.06_cn allows remote attackers to crash the router via HTTP. Published material identifies the list parameter at /goform/SetVirtualServerCfg but does not disclose the exact unsafe copy operation. The endpoint requires no authentication, and device testing records a real crash rather than demonstrated code execution.

The record

CVE
CVE-2023-40895
Published
Aug 24, 2023
Updated
Oct 3, 2024
Vendor
Shenzhen Tenda Technology Co., Ltd.
Product
AC8 v4.0
Classifications
CWE-787, T1210
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 24, 2023CVE publishedPublication date reported by the CVE source.
  2. Oct 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?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=si_V16.03.34.06_cn

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Shenzhen Tenda Technology Co., Ltd. · AC8 v4.0version=si_V16.03.34.06_cn

Published CVSS scores

9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/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 exploitUnconfirmed

Weakness, pattern, technique

CWE-787Out-of-bounds Write
T1210Exploitation of Remote Services

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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