A stack overflow vulnerability exists in the WebCam Server Login functionality of GeoVision GV-VMS V20 20.0.2. A specially crafted HTTP request can lead to an arbitrary code execution. An attacker can make an unauthenticated HTTP request to trigger this vulnerability. #### Stack-overflow via unconstrained sscanf The call to `sscanf` at [1] to split the `Buffer` variable into the `username` and `password` variables doesn't limit the size of the extracted content to match the destination buffers' sizes. In this case, if either the username or password decoded from the authorization string exceeds `40` characters (the size the stack variables `username` and `password`) then a stack overflow will occur. The data is controlled by an attacker, but sronger constraints (e.g. no null bytes) may make exploitation harder. A successful attack could lead to full code execution as SYSTEM on the machine running the service.
Fix
Patch, vendor advisory and mitigation references on NVD 1
- https://www.geovision.com.tw/cyber_security.php Vendor Advisory
Every line above is quoted from NVD, CISA, Microsoft, the vendor's own advisory or DISA; nothing is generated.
Change history 1
- First seenCVSS 9.0 · geovisionNVD modified 2026-10-26 20:10
Affected (CPE criteria) 1
cpe:2.3:o:geovision:gv-vms_firmware:*:*:*:*:*:*:*:*
References 2
- https://talosintelligence.com/vulnerability_reports/ Third Party Advisory
- https://www.geovision.com.tw/cyber_security.php Vendor Advisory