CVE-2021-4464 CRITICAL

CVE-2021-4464: FIberHome AN5506-04-FA / HG6245D Routers Remote Stack Overflow

Vendor Fiberhome
Product AN5506-04-FA
Weakness CWE-121
Published November 12, 2025
Last update November 21, 2025
View on NVD All CVEs

CVSS base score

9.3/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality —
Integrity —

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

What the vulnerability does

01Description

FiberHome AN5506-04-FA firmware versions up to and including RP2631 and HG6245D prior to RP2602 contain a stack-based buffer overflow, as the HTTP service ('webs') fails to enforce maximum lengths for Cookie header values. When a cookie longer than 511 bytes is processed, a stack buffer is overrun, leading to a crash or potential control of execution flow.

Key dates

02Disclosure timeline

November 12, 2025 CVE published
November 21, 2025 Record updated