How severe is CVE-2017-14420?

CVE-2017-14420 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2017-14420 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (40th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2017-14420?

CVE-2017-14420 affects Dlink Dir-850l Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2017-14420?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2017-14420 published?

CVE-2017-14420 was published on 2017-09-13 and last updated on 2026-06-17.

CVE-2017-14420

CVE-2017-14420 is a medium-severity vulnerability in Dlink Dir-850l Firmware with a CVSS 3.x base score of 5.9. 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-295.

Key facts

Severity: Medium (CVSS 3.x base score 5.9)
CVSS v2: 4.3
EPSS exploit prediction: 1% (40th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-295
Affected product: Dlink Dir-850l Firmware
Published: 2017-09-13
Last modified: 2026-06-17

Description

The D-Link NPAPI extension, as used on D-Link DIR-850L REV. A (with firmware through FW114WWb07_h2ab_beta1) and REV. B (with firmware through FW208WWb02) devices, does not verify X.509 certificates from SSL servers, which allows man-in-the-middle attackers to spoof servers and obtain sensitive information via a crafted certificate.

Frequently asked questions

What is CVE-2017-14420?: The D-Link NPAPI extension, as used on D-Link DIR-850L REV. A (with firmware through FW114WWb07_h2ab_beta1) and REV. B (with firmware through FW208WWb02) devices, does not verify X.509 certificates from SSL servers, which allows man-in-the-middle attackers to spoof servers and obtain sensitive information via a crafted certificate.
How severe is CVE-2017-14420?: CVE-2017-14420 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2017-14420 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (40th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2017-14420?: CVE-2017-14420 affects Dlink Dir-850l Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2017-14420?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2017-14420 published?: CVE-2017-14420 was published on 2017-09-13 and last updated on 2026-06-17.

References

https://pierrekim.github.io/blog/2017-09-08-dlink-850l-mydlink-cloud-0days-vulnerabilities.html

Affected products (1)

cpe:2.3:o:dlink:dir-850l_firmware:*:*:*:*:*:*:*:*

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