CVE-2023-43240Public exploitNetwork attack vector

Service crash via oversized sip_address parameter

Published Sep 21, 2023 · Updated Sep 25, 2024

Stack overflow in ipportFilter in D-Link DIR-816 A2 1.10CNB05 allows remote attackers to crash the GoAhead process via HTTP. The proof of concept posts a 10,000-byte sip_address value to /goform/ipportFilter, overflowing the stack because input length is used as the copy bound. The request needs a token retrieved from the login page; a process crash is demonstrated, while code execution is claimed but not demonstrated.

CVSS severity9.8
Critical
EPSS probability12.24%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stack overflow in ipportFilter in D-Link DIR-816 A2 1.10CNB05 allows remote attackers to crash the GoAhead process via HTTP. The proof of concept posts a 10,000-byte sip_address value to /goform/ipportFilter, overflowing the stack because input length is used as the copy bound. The request needs a token retrieved from the login page; a process crash is demonstrated, while code execution is claimed but not demonstrated.

The record

CVE
CVE-2023-43240
Published
Sep 21, 2023
Updated
Sep 25, 2024
Vendor
D-Link
Product
DIR-816
Classifications
CWE-787, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 21, 2023CVE publishedPublication date reported by the CVE source.
  2. Sep 25, 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=v1.10cnb05

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

D-Link · DIR-816version=v1.10cnb05

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

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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
T1499.004Endpoint Denial of Service: Application 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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