CVE-2023-38823Public exploitNetwork attack vector

Unauthenticated code execution via oversized configuration value

Published Nov 20, 2023 · Updated Jun 10, 2025

Buffer overflow in Tenda AC19 v1.0, AC18, AC9 v1.0, and AC6 v1.0 and v2.0 allows remote attackers to execute arbitrary code. The /bin/httpd formSetCfm handler accepts an arbitrarily long value for a chosen key, and GetValue later reads that value into a fixed-size buffer. No authentication or user interaction is required; a crafted POST to /goform/setcfm can overwrite memory, execute commands, or crash the router.

CVSS severity9.8
Critical
EPSS probability1.20%
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 AC19 v1.0, AC18, AC9 v1.0, and AC6 v1.0 and v2.0 allows remote attackers to execute arbitrary code. The /bin/httpd formSetCfm handler accepts an arbitrarily long value for a chosen key, and GetValue later reads that value into a fixed-size buffer. No authentication or user interaction is required; a crafted POST to /goform/setcfm can overwrite memory, execute commands, or crash the router.

The record

CVE
CVE-2023-38823
Published
Nov 20, 2023
Updated
Jun 10, 2025
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-120, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Nov 20, 2023CVE publishedPublication date reported by the CVE source.
  2. Jun 10, 2025Record 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

9.8CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
9.8NVDCVSS: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 exploitPublished

Weakness, pattern, technique

CWE-120Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
T1190Exploit Public-Facing Application

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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