FiberHome AN5506-04-FA/HG6245D HTTP Service Cookie stack-based overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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9.8$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as critical, was found in FiberHome AN5506-04-FA and HG6245D. This issue affects some unknown processing of the component HTTP Service. The manipulation of the argument Cookie results in stack-based overflow. This vulnerability is reported as CVE-2021-4464. The attack can be launched remotely. No exploit exists.

Detailsinfo

A vulnerability, which was classified as very critical, was found in FiberHome AN5506-04-FA and HG6245D (affected version not known). Affected is some unknown functionality of the component HTTP Service. The manipulation of the argument Cookie with an unknown input leads to a stack-based overflow vulnerability. CWE is classifying the issue as CWE-121. A stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function). This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

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 weakness was disclosed by Pierre Barre. The advisory is shared for download at pierrekim.github.io. This vulnerability is traded as CVE-2021-4464 since 11/12/2025. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 11/13/2025).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Vendor

Name

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 9.8
VulDB Meta Temp Score: 9.8

VulDB Base Score: 9.8
VulDB Temp Score: 9.8
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Stack-based overflow
CWE: CWE-121 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

11/12/2025 CVE reserved
11/13/2025 +1 days Advisory disclosed
11/13/2025 +0 days VulDB entry created
11/13/2025 +0 days VulDB entry last update

Sourcesinfo

Advisory: pierrekim.github.io
Researcher: Pierre Barre
Status: Not defined

CVE: CVE-2021-4464 (🔒)
GCVE (CVE): GCVE-0-2021-4464
GCVE (VulDB): GCVE-100-332292

Entryinfo

Created: 11/13/2025 07:47
Changes: 11/13/2025 07:47 (66)
Complete: 🔍
Cache ID: 216::103

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