What is CVE-2020-9275?

CVE-2020-9275 is a critical-severity vulnerability in Dlink Dsl-2640b, classified under Missing Authentication for Critical Function. CVSS score: 9.8/10. Published 2020-04-20.

How severe is CVE-2020-9275?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Auth bypass in Dlink Dsl-2640b

CVE-2020-9275

An issue was discovered on D-Link DSL-2640B B2 EU_4.01B devices. A cfm UDP service listening on port 65002 allows remote, unauthenticated exfiltration of administrative credentials.

Vulnerability class: Broken Authentication

Published 2020-04-20 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.017 (76.4th percentile), scored 2026-10-01.

Low probability of exploitation in the next 30 days, but still tracked. 76th percentile — 76.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.017 · newest: 0.017 · change: 0.000

Affected products

Dlink Dsl-2640b
Dlink Dsl-2640b Firmware — versions eu_4.01b

Weakness classification (CWE)

CWE-306 — Missing Authentication for Critical Function

References

www.dlink.com/en/security-bulletin (Vendor Advisory)
raelize.com/posts/d-link-dsl-2640b-security-advisories/ (Exploit, Third Party Advisory)
raelize.com/advisories/CVE-2020-9275_D-Link-DSL-2640B_Remote-Credentials-Exfilt… (Third Party Advisory)

Frequently asked questions

What is CVE-2020-9275?: CVE-2020-9275 is a critical-severity vulnerability in Dlink Dsl-2640b, classified under Missing Authentication for Critical Function. CVSS score: 9.8/10. Published 2020-04-20.
How severe is CVE-2020-9275?: Critical severity. CVSS v3 base score is 9.8 out of 10.