How severe is CVE-2023-39666?

CVE-2023-39666 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-2023-39666 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-39666?

CVE-2023-39666 affects Dlink Dir-842 Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-39666?

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-2023-39666 published?

CVE-2023-39666 was published on 2023-08-18 and last updated on 2026-06-17.

CVE-2023-39666

CVE-2023-39666 is a critical-severity vulnerability in Dlink Dir-842 Firmware with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-120.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 1% (63rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-120
Affected product: Dlink Dir-842 Firmware
Published: 2023-08-18
Last modified: 2026-06-17

Description

D-Link DIR-842 fw_revA_1-02_eu_multi_20151008 was discovered to contain multiple buffer overflows in the fgets function via the acStack_120 and acStack_220 parameters.

Frequently asked questions

What is CVE-2023-39666?: D-Link DIR-842 fw_revA_1-02_eu_multi_20151008 was discovered to contain multiple buffer overflows in the fgets function via the acStack_120 and acStack_220 parameters.
How severe is CVE-2023-39666?: CVE-2023-39666 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-2023-39666 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-39666?: CVE-2023-39666 affects Dlink Dir-842 Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-39666?: 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-2023-39666 published?: CVE-2023-39666 was published on 2023-08-18 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:dlink:dir-842_firmware:1.05b02:*:*:*:*:*:*:*

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