openNDS before 11.0.0 is susceptible to unauthenticated OS command execution via shell command injection through the fas query parameter on the /openndspreauth/ endpoint because of libopennds.sh.

In openNDS before 11.0.0, the clientparams.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.

An issue was discovered in the captive portal in OpenNDS before version 10.1.3. It has multiple memory leaks due to not freeing up allocated memory. This may lead to a Denial-of-Service condition due to the consumption of all available memory. Affected OpenNDS before version 10.1.3 fixed in OpenWrt master and OpenWrt 23.05 on 23. November by updating OpenNDS to version 10.2.0.

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 httpmicrohttpd.c.

Last updated 3 March 2025

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.