How severe is CVE-2023-43239?

CVE-2023-43239 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2023-43239 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 12% (96th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-43239?

CVE-2023-43239 affects Dlink Dir-816 A2 Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-43239?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2023-43239 published?

CVE-2023-43239 was published on 2023-09-21 and last updated on 2026-06-17.

CVE-2023-43239

CVE-2023-43239 is a critical-severity vulnerability in Dlink Dir-816 A2 Firmware with a CVSS 3.x base score of 9.8. Its EPSS exploit-prediction score of 12% places it in the 96th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-787.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 12% (96th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Dlink Dir-816 A2 Firmware
Published: 2023-09-21
Last modified: 2026-06-17

Description

D-Link DIR-816 A2 v1.10CNB05 was discovered to contain a stack overflow via parameter flag_5G in showMACfilterMAC.

Frequently asked questions

What is CVE-2023-43239?: D-Link DIR-816 A2 v1.10CNB05 was discovered to contain a stack overflow via parameter flag_5G in showMACfilterMAC.
How severe is CVE-2023-43239?: CVE-2023-43239 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2023-43239 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 12% (96th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-43239?: CVE-2023-43239 affects Dlink Dir-816 A2 Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-43239?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2023-43239 published?: CVE-2023-43239 was published on 2023-09-21 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:dlink:dir-816_a2_firmware:1.10cnb05:*:*:*:*:*:*:*

More vulnerabilities in Dlink Dir-816 A2 Firmware

CVE-2023-43240 — Critical (CVSS 9.8): D-Link DIR-816 A2 v1.10CNB05 was discovered to contain a stack overflow via parameter sip_address in ipportFilter.
CVE-2023-43238 — Critical (CVSS 9.8): D-Link DIR-816 A2 v1.10CNB05 was discovered to contain a stack overflow via parameter nvmacaddr in form2Dhcpip.cgi.
CVE-2023-43237 — Critical (CVSS 9.8): D-Link DIR-816 A2 v1.10CNB05 was discovered to contain a stack overflow via parameter macCloneMac in setMAC.
CVE-2023-43236 — Critical (CVSS 9.8): D-Link DIR-816 A2 v1.10CNB05 was discovered to contain a stack overflow via parameter statuscheckpppoeuser in…
CVE-2018-17068 — Critical (CVSS 9.8): An issue was discovered on D-Link DIR-816 A2 1.10 B05 devices. An HTTP request parameter is used in command string…
CVE-2018-17067 — Critical (CVSS 9.8): An issue was discovered on D-Link DIR-816 A2 1.10 B05 devices. A very long password to /goform/formLogin could lead to…

All CVEs affecting Dlink Dir-816 A2 Firmware →

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