CVE-2021-35395

Realtek AP-Router SDK — Realtek AP-Router SDK Buffer Overflow Vulnerability
🔥 CVSS 3.1  9.8 / 10 — CRITICAL 🔴 CISA Known Exploited Vulnerability

Overview

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).

https://nvd.nist.gov/vuln/detail/CVE-2021-35395

Key Details

PropertyValue
CVE ID CVE-2021-35395
Vendor / Product Realtek — AP-Router SDK
NVD Published2021-08-16
NVD Last Modified2025-11-07
CVSS 3.1 Score9.8
CVSS 3.1 VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
SeverityCRITICAL
CISA KEV Added2021-11-03
CISA KEV Deadline2021-11-17
Known Ransomware Use No

CVSS 3.1 Breakdown

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

Required Action

CISA BOD 22-01 Deadline: 2021-11-17. Apply updates per vendor instructions.

Timeline

DateEvent
2021-11-03Added to CISA Known Exploited Vulnerabilities catalog
2021-11-17CISA BOD 22-01 remediation deadline

References

ResourceType
NVD — CVE-2021-35395 Vulnerability Database
CISA KEV Catalog Entry US Government