CVE-2025-8760: 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…

PriorityP263critical9.8CVSS 3.1

AVNACLPRNUINSUCHIHAH

EPSS

0.70%

48.4th percentile

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.

Affected

2 ranges

Vendor	Product	Version range	Fixed in
instar	2k	—	—
instar	4k	—	—

CVSS provenance

nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

nvdv4.09.3CRITICALCVSS:4.0/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

nvdv2.010.0CRITICALAV:N/AC:L/Au:N/C:C/I:C/A:C

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