Vulnerability · 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
Published Nov 12, 2025 · catalog updated Nov 21, 2025 · FiberHome HG6245D
Last checked Nov 3, 2026. A connected source was read within the last 7 days.
Check if you run it
No confirmed exploitation is on record for CVE-2021-4464. EPSS is 2.18%. Act only if a listed version of FiberHome HG6245D is installed.
Gaps on this record
- No vendor fix or required action is stored. Compare the linked advisory before you change production.
- Severity
- Critical9.3
- Known exploitation
- Not in CISA/VulnCheck KEV
- EPSS
- 2.18%
- Remediation
- Version ranges on file
- Affected products
- vendor FiberHome HG6245D 0 <RP2602
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.
Are you affected?
Enter the version you run. The result uses only the ranges stored on this record.
The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.
- vendor FiberHome HG6245D 0 <RP26020 <RP2602
How to fix CVE-2021-4464
Upgrade
CVE-2021-4464 lists a fix boundary at RP2602. Compare the installed build with that boundary before you change production.
Version check
Seen in 0 <RP2602
Advisory
Open the cve_org record and follow its fix.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
No confirmed exploitation is on record for CVE-2021-4464. EPSS is 2.18%. Act only if a listed version of FiberHome HG6245D is installed.
Which versions are affected?
Compare what you have installed with FiberHome HG6245D 0 <RP2602 0 <RP2602. Compare the installed version with the linked vendor advisory before you change production.
What should an analyst verify?
No weakness class is stored. EPSS 2.18%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Code
The project this record applies to. Exploit listings stay in References.
No public source repository is identified for this product.
Timeline
Detection, updates, and resolution for this record.
Nov 12, 2025 · EUVD
Detected
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.
Nov 21, 2025 · EUVD
Updated
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.
Sources
- CVE.orgVulnerability recordCVE-2021-4464
Official CVE identifier
cve.org - EUVDVulnerability recordEUVD-2021-34714
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
euvd.enisa.europa.eu
References
Freshness
Last verified in this catalog Nov 3, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.
- CVE.orgOct 25, 2026
- EUVDOct 25, 2026