CVE-2026-38820
HighCVSS 8.3Exploitation Probability (EPSS)
High risk76th percentile - higher than 76% of all known CVEs
Summary
openNDS before 11.0.0 is susceptible to unauthenticated OS command execution via shell command injection through the fas query parameter on the /opennds_preauth/ endpoint because of libopennds.sh.
Risk Assessment
An unauthenticated attacker can execute arbitrary commands on the server, potentially leading to full system compromise and network security breach.
Recommendation
Update openNDS to version 11.0.0 or later and secure the /opennds_preauth/ endpoint against unauthorized access.
Other vulnerabilities in openNDS
See all- CVE-2026-38822High
In openNDS before 11.0.0, the client_params.sh script, invoked by the openNDS daemon to serve the authenticated client status page, is vulnerable to OS command injection through crafted HTTP GET query parameter keys. An authenticated captive portal user can inject arbitrary shell commands by embedding semicolons in a URL query parameter name.
- CVE-2026-38821High
A heap-based buffer overflow vulnerability exists in openNDS before 11.0.0 that allows an unauthenticated attacker on the captive portal network to crash the openNDS daemon (denial of service) and potentially achieve remote code execution. This is in http_microhttpd.c.
- CVE-2026-38819Medium
Multiple memory leaks in openNDS before 11.0.0 allow an unauthenticated attacker on the captive portal network to exhaust all available memory on the device within minutes.
Original NVD description (English source)
openNDS before 11.0.0 is susceptible to unauthenticated OS command execution via shell command injection through the fas query parameter on the /opennds_preauth/ endpoint because of libopennds.sh.