10
/ 10
CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
Description
GV-VMS V20 is a Video Monitoring Software used to gather the feeds of many surveillance cameras and manage other security devices. It is a native application accessed locally, but it is also possible to enable remote access via the "WebCam Server" feature. Once enabled, it is possible to access to the management and monitoring feature via a regular Web interface. This webersever is another native application, compiled without ASLR, which makes exploitation much easier and more likely.
Most of the features require authentication before being reachable and leverage a standard login page to grant access. However the `gvapi` endpoint uses its own authentication mechanism via an `HTTP Authorization` header. It supports both `Basic` authentication and the `Digest` modes of authentication.
#### Stack-overflow via unbound copy of base64 decoded string
The `b64decoder` string is sized dynamically, but it is then copied to the `Buffer` stack variable one character at the time at [0], and there's no bound-check. As such, if the decoded string is bigger than 256 characters (the size of the `Buffer` variable) then a stack overflow occurs. Because the data can be fully controlled by an attacker and lack of ASLR, this vulnerability can easily be exploited to gain full code execution as SYSTEM on the machine running the service.
Most of the features require authentication before being reachable and leverage a standard login page to grant access. However the `gvapi` endpoint uses its own authentication mechanism via an `HTTP Authorization` header. It supports both `Basic` authentication and the `Digest` modes of authentication.
#### Stack-overflow via unbound copy of base64 decoded string
The `b64decoder` string is sized dynamically, but it is then copied to the `Buffer` stack variable one character at the time at [0], and there's no bound-check. As such, if the decoded string is bigger than 256 characters (the size of the `Buffer` variable) then a stack overflow occurs. Because the data can be fully controlled by an attacker and lack of ASLR, this vulnerability can easily be exploited to gain full code execution as SYSTEM on the machine running the service.
AI Analysis
Stack-overflow vulnerability in GeoVision GV-VMS V20 WebCam Server via unbound copy of base64 decoded string, allowing for full code execution as SYSTEM on the machine running the service.
Basic Information
ID
CVE-2026-42369
Source
GV
Published
May 4, 2026 at 00:47
Affected Product
Vendor
GeoVision Inc.
Product
GV-VMS V20.0.2
Version
V20.0.2
Affected Versions
GeoVision Inc. GV-VMS V20.0.2 V20.0.2
CWE Classification
AI Assessment
AI Score
10 / 10
AI Severity
Critical
Vendor
GeoVision Inc.
Product
GV-VMS V20.0.2
Version
V20.0.2