CVE-2021-35395Actively exploitedAdded to KEV 2021-11-03

Realtek AP-Router SDK Buffer Overflow Vulnerability

Realtek, AP-Router SDK

Description

Realtek AP-Router SDK HTTP web server boa contains a buffer overflow vulnerability due to unsafe copies of some overly long parameters submitted in the form that lead to denial-of-service (DoS).

CVSS severity for this advisory hasn't been enriched from NVD yet, check back shortly.

EPSS, exploit probability

Critical

98.1%

estimated chance of real-world exploitation in the next 30 days, higher than 99.9% of every CVE FIRST.org scores

Refreshed 10/28/2026, via FIRST.org's EPSS model, not CVSS, this measures likelihood of exploitation, not how severe it would be.

Required action

Apply updates per vendor instructions.

CISA-recommended due date: 2021-11-17

CWE-20 CWE-122

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