{"cve":"CVE-2021-4464","nvd":{"published":"2025-11-12T22:15:42.027","modified":"2026-06-17T04:19:48.850","status":"Deferred","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.","cvss_v4":{"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","score":9.3},"cvss_v3":null,"cwes":["CWE-121"],"references":["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"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:16:02.354564667+00:00"},"epss":{"cve":"CVE-2021-4464","score":0.02177,"percentile":0.82335,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}