An issue was discovered on D-Link DSL-2640B B2 EU_4.01B devices.

published 2020-04-20 6y ago modified 2026-06-17 4mo ago also EUVD-2020-30105

cvss: 8.8; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 2.6%; EPSS 2.6% chance of exploitation in 30 days, percentile 85%
public exploits: 0; none known

An issue was discovered on D-Link DSL-2640B B2 EU_4.01B devices. The function do_cgi(), which processes cgi requests supplied to the device's web servers, is vulnerable to a remotely exploitable stack-based buffer overflow. Unauthenticated exploitation is possible by combining this vulnerability with CVE-2020-9277.

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Exploit prediction

2.60% chance of exploitation in the next 30 days, higher than 85% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

raelize.com https://raelize.com/posts/d-link-dsl-2640b-security-advisories/ referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
NVD	3.1	8.8	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
NVD	2.0	9.0	AV:N/AC:L/Au:S/C:C/I:C/A:C

Classification

Weakness

CWE-787 Out-of-bounds Write

References

raelize.com /posts/d-link-dsl-2640b-security-advisories/
exploit, third-party-advisory
dlink.com /en/security-bulletin
vendor-advisory
raelize.com /advisories/CVE-2020-9276_D-Link-DSL-2640B_do_cgi-buffer-overflow_v1.0.txt
third-party-advisory

Sources

CVE List CVE-2020-9276
NVD CVE-2020-9276

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