What is CVE-2026-91001?

CVE-2026-91001 is a critical-severity vulnerability in D-Link Di-8400, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 9.9/10. Published 2026-09-15.

How severe is CVE-2026-91001?

Critical severity. CVSS v3 base score is 9.9 out of 10.

Buffer overflow in D-Link Di-8400

CVE-2026-91001

A security flaw has been discovered in D-Link DI-8400 16.07. This affects the function ddns_asp of the file /ddns.asp of the component DDNS Configuration. Performing a manipulation of the argument serv/user/host/wild/mx/bmx/cust/ip results in stack-based buffer overflow. The attack can be initiated remotely. The exploit has been released to the public and may be used for attacks.

Vulnerability class: Buffer Overflow

CVSS v3 metric

CVSS v3 base score 9.9 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H.

Affected products

D-link Di-8400 — versions 16.07

Weakness classification (CWE)

References

cna@vuldb.com (technical-description, vdb-entry)
cna@vuldb.com (signature, permissions-required)
cna@vuldb.com (third-party-advisory)
cna@vuldb.com (third-party-advisory)
cna@vuldb.com (related)
cna@vuldb.com (exploit)
cna@vuldb.com (product)

Frequently asked questions

What is CVE-2026-91001?: CVE-2026-91001 is a critical-severity vulnerability in D-Link Di-8400, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 9.9/10. Published 2026-09-15.
How severe is CVE-2026-91001?: Critical severity. CVSS v3 base score is 9.9 out of 10.