CVE-2021-4464 - CVE House
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Status published Critical CVE-2021-4464

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

Vulnerability Description

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.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:

  • Pierre Barre

References

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Affected Vendor

Affected Software

AN5506-04-FA, HG6245D
Vulnerable Versions:
0

Timeline

Official Publish: November 12th, 2025
Last Modified: November 21st, 2025
Added to House: July 21st, 2026

CVSS Vectors

Weaknesses (CWE)

CWE-121

MITRE ATT&CK TTPs

T1190 Exploit Public-Facing Application
Initial Access
T1068 Exploitation for Privilege Escalation
Privilege Escalation
T1055 Process Injection
Defense Evasion
T1105 Ingress Tool Transfer
Command and Control
T1485 Data Destruction
Impact