CVE-2021-4464

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.

CVSS

No CVSS.

References

Link	Resource
https://pierrekim.github.io/advisories/2021-fiberhome-0x00-ont.txt
https://pierrekim.github.io/blog/2021-01-12-fiberhome-ont-0day-vulnerabilities.html#misc-remote-stack-overflow-an5506
https://www.vulncheck.com/advisories/fiberhome-routers-remote-stack-overflow

Configurations

No configuration.

History

12 Nov 2025, 22:15

Type	Values Removed	Values Added
New CVE

Information

Published : 2025-11-12 22:15

Updated : 2025-11-14 16:42

NVD link : CVE-2021-4464

Mitre link : CVE-2021-4464

CVE.ORG link : CVE-2021-4464

JSON object : View

Products Affected

No product.

CWE

CWE-121

Stack-based Buffer Overflow

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