CVE-2021-4464CWE-121

FIberHome AN5506-04-FA / HG6245D Routers Remote Stack Overflow

Critical · published November 12, 2025

CVSS v4.0
9.3
EPSS
2%
Percentile
82.2
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v4.0
9.3 · CRITICAL
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
EPSS
0.02177 · 82.2th percentile
Weakness
CWE-121 · Stack-based Buffer Overflow
Published
2025-11-12T22:09Z
EPSS history
Timeline
  • 12 NOV 22:09Z
    FIberHome AN5506-04-FA / HG6245D Routers Remote Stack Overflow
    cvelistv5