Realtek AP-Router SDK Buffer Overflow Vulnerability

Added to KEV
2021-11-03
Federal due date
2021-11-17
Vendor
Realtek
Product
AP-Router SDK
EPSS
99.9th percentile (score 0.937, as of 2026-06-08)
NVD CVSS v3.1
Ransomware use
Unknown
Upstream
https://nvd.nist.gov/vuln/detail/CVE-2021-35395

CISA short 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).

Required action

Apply updates per vendor instructions.

EPSS percentile is the FIRST.org exploit-probability ranking as of the date noted above; it moves daily. CVSS reflects NVD's analysis at time of publication.