D-Link DIR-2640-US 1.01B04 is vulnerable to Buffer Overflow.

published 2021-06-16 5y ago modified 2026-07-09 4mo ago also EUVD-2021-20863

cvss: 7.1; 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 45%
public exploits: 0; none known

D-Link DIR-2640-US 1.01B04 is vulnerable to Buffer Overflow. There are multiple out-of-bounds vulnerabilities in some processes of D-Link AC2600(DIR-2640). Local ordinary users can overwrite the global variables in the .bss section, causing the process crashes or changes.

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Exploit prediction

0.54% chance of exploitation in the next 30 days, higher than 45% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

github.com https://github.com/liyansong2018/CVE/tree/main/2021/CVE-2021-34201 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
NVD	3.1	7.1	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
NVD	2.0	3.6	AV:L/AC:L/Au:N/C:N/I:P/A:P

Classification

Weakness

CWE-787 Out-of-bounds Write

References

github.com /liyansong2018/CVE/tree/main/2021/CVE-2021-34201
exploit, third-party-advisory
dlink.com /en/security-bulletin/
vendor-advisory

Sources

CVE List CVE-2021-34201
NVD CVE-2021-34201

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