The D-Link NPAPI extension, as used on D-Link DIR-850L REV.

published 2017-09-13 9y ago modified 2026-06-17 4mo ago also EUVD-2017-5923

cvss: 5.9; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 0.5%; EPSS 0.5% chance of exploitation in 30 days, percentile 43%
public exploits: 0; none known

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.

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Exploit prediction

0.51% chance of exploitation in the next 30 days, higher than 43% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

pierrekim.github.io https://pierrekim.github.io/blog/2017-09-08-dlink-850l-mydlink-cloud-0days-vulnerabilities.html referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
NVD	3.1	5.9	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
NVD	2.0	4.3	AV:N/AC:M/Au:N/C:P/I:N/A:N

Classification

Weakness

CWE-295 Improper Certificate Validation

References

pierrekim.github.io /blog/2017-09-08-dlink-850l-mydlink-cloud-0days-vulnerabilities.html
exploit, third-party-advisory

Sources

CVE List CVE-2017-14420
NVD CVE-2017-14420

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