10.0
HIGH CVSS 2.0
CVE-2025-8760
INSTAR 2K+/4K fcgi_server base64_decode buffer overflow
Description

A vulnerability was identified in INSTAR 2K+ and 4K 3.11.1 Build 1124. This affects the function base64_decode of the component fcgi_server. The manipulation of the argument Authorization leads to buffer overflow. It is possible to initiate the attack remotely.

INFO

Published Date :

Aug. 13, 2025, 7:15 a.m.

Last Modified :

Aug. 13, 2025, 5:33 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2025-8760 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 2.0 HIGH [email protected]
CVSS 3.1 CRITICAL [email protected]
CVSS 4.0 CRITICAL [email protected]
Solution
Update firmware to patch buffer overflow vulnerability in fcgi_server component.
  • Update the INSTAR 2K+ and 4K firmware.
  • Apply security patches provided by the vendor.
  • Limit access to the affected component.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2025-8760.

URL Resource
https://modzero.com/static/MZ-25-03_modzero_INSTAR.pdf
https://vuldb.com/?ctiid.319863
https://vuldb.com/?id.319863
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2025-8760 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2025-8760 weaknesses.

CAPEC-8: Buffer Overflow in an API Call Buffer Overflow in an API Call CAPEC-9: Buffer Overflow in Local Command-Line Utilities Buffer Overflow in Local Command-Line Utilities CAPEC-10: Buffer Overflow via Environment Variables Buffer Overflow via Environment Variables CAPEC-14: Client-side Injection-induced Buffer Overflow Client-side Injection-induced Buffer Overflow CAPEC-24: Filter Failure through Buffer Overflow Filter Failure through Buffer Overflow CAPEC-42: MIME Conversion MIME Conversion CAPEC-44: Overflow Binary Resource File Overflow Binary Resource File CAPEC-45: Buffer Overflow via Symbolic Links Buffer Overflow via Symbolic Links CAPEC-46: Overflow Variables and Tags Overflow Variables and Tags CAPEC-47: Buffer Overflow via Parameter Expansion Buffer Overflow via Parameter Expansion CAPEC-100: Overflow Buffers Overflow Buffers CAPEC-123: Buffer Manipulation Buffer Manipulation CAPEC-8: Buffer Overflow in an API Call Buffer Overflow in an API Call CAPEC-9: Buffer Overflow in Local Command-Line Utilities Buffer Overflow in Local Command-Line Utilities CAPEC-10: Buffer Overflow via Environment Variables Buffer Overflow via Environment Variables CAPEC-14: Client-side Injection-induced Buffer Overflow Client-side Injection-induced Buffer Overflow CAPEC-24: Filter Failure through Buffer Overflow Filter Failure through Buffer Overflow CAPEC-42: MIME Conversion MIME Conversion CAPEC-44: Overflow Binary Resource File Overflow Binary Resource File CAPEC-45: Buffer Overflow via Symbolic Links Buffer Overflow via Symbolic Links CAPEC-46: Overflow Variables and Tags Overflow Variables and Tags CAPEC-47: Buffer Overflow via Parameter Expansion Buffer Overflow via Parameter Expansion CAPEC-67: String Format Overflow in syslog() String Format Overflow in syslog() CAPEC-92: Forced Integer Overflow Forced Integer Overflow CAPEC-100: Overflow Buffers Overflow Buffers

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2025-8760 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2025-8760 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Aug. 13, 2025

    Action Type Old Value New Value
    Added Description A vulnerability was identified in INSTAR 2K+ and 4K 3.11.1 Build 1124. This affects the function base64_decode of the component fcgi_server. The manipulation of the argument Authorization leads to buffer overflow. It is possible to initiate the attack remotely.
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
    Added CVSS V2 (AV:N/AC:L/Au:N/C:C/I:C/A:C)
    Added CWE CWE-119
    Added CWE CWE-120
    Added Reference https://modzero.com/static/MZ-25-03_modzero_INSTAR.pdf
    Added Reference https://vuldb.com/?ctiid.319863
    Added Reference https://vuldb.com/?id.319863
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
Vulnerability Scoring Details
Base CVSS Score: 9.3
Attack Vector
Attack Complexity
Attack Requirements
Privileges Required
User Interaction
VS Confidentiality
VS Integrity
VS Availability
SS Confidentiality
SS Integrity
SS Availability
Base CVSS Score: 9.8
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality Impact
Integrity Impact
Availability Impact
Base CVSS Score: 10
Access Vector
Access Complexity
Authentication
Confidentiality Impact
Integrity Impact
Availability Impact