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.

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.

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.

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.

Last updated 3 March 2025

An issue was discovered in OpenNDS before 10.1.3. It fails to sanitize the gateway FQDN entry in the configuration file, allowing attackers that have direct or indirect access to this file to execute arbitrary OS commands.

An issue was discovered in OpenNDS before 10.1.3. It fails to sanitize the network interface name entry in the configuration file, allowing attackers that have direct or indirect access to this file to execute arbitrary OS commands.

An issue was discovered in OpenNDS before 10.1.3. It fails to sanitize the status path script entry in the configuration file, allowing attackers that have direct or indirect access to this file to execute arbitrary OS commands.

An issue was discovered in OpenNDS before 10.1.3. It fails to sanitize the FAS key entry in the configuration file, allowing attackers that have direct or indirect access to this file to execute arbitrary OS commands.

The ACEManager component of ALEOS 4.16 and earlier does not

perform input sanitization during authentication, which could

potentially result in a Denial of Service (DoS) condition for

ACEManager without impairing other router functions. ACEManager

recovers from the DoS condition by restarting within ten seconds of

becoming unavailable.

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.

An issue was discovered in the captive portal in OpenNDS before version 10.1.3. getquery in httpmicrohttpd.c does not validate the length of the query string of GET requests. This leads to a stack-based buffer overflow in versions 9.x and earlier, and to a heap-based buffer overflow in versions 10.x and later. Attackers may exploit the issue to crash OpenNDS (Denial-of-Service condition) or to inject and execute arbitrary bytecode (Remote Code Execution). 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.

An issue was discovered in OpenNDS Captive Portal before 10.1.2. it has a dobinauth NULL pointer dereference that can be triggered with a crafted GET HTTP request with a missing client redirect query string parameter. Triggering this issue results in crashing openNDS (a Denial-of-Service condition). The issue occurs when the client is about to be authenticated, and can be triggered only when the BinAuth option is set. Affected OpenNDS Captive Portal before version 10.1.2 fixed infixed in OpenWrt master, OpenWrt 23.05 and OpenWrt 22.03 on28. August 2023 by updating OpenNDS to version 10.1.3.

An issue was discovered in OpenNDS Captive Portal before version 10.1.2. It has a NULL pointer dereference in preauthenticated() that can be triggered with a crafted GET HTTP request with a missing redirect query string parameter. Triggering this issue results in crashing OpenNDS (a Denial-of-Service condition). Affected OpenNDS Captive Portal before version 10.1.2 fixed infixed in OpenWrt master, OpenWrt 23.05 and OpenWrt 22.03 on28. August 2023 by updating OpenNDS to version 10.1.3.

An issue was discovered in OpenNDS Captive Portal before version 10.1.2. It has a showpreauthpage NULL pointer dereference that can be triggered with a crafted GET HTTP with a missing User-Agent header. Triggering this issue results in crashing OpenNDS (a Denial-of-Service condition). This problem was fixed in OpenWrt master, OpenWrt 23.05 and OpenWrt 22.03 on 28. August 2023 by updating OpenNDS to version 10.1.3.

An issue was discovered in OpenNDS Captive Portal before version 10.1.2. It has a trytoauthenticate NULL pointer dereference that can be triggered with a crafted GET HTTP with a missing client token query string parameter. Triggering this issue results in crashing OpenNDS (a Denial-of-Service condition). Affected OpenNDS Captive Portal before version 10.1.2 fixed in OpenWrt master, OpenWrt 23.05 and OpenWrt 22.03 on 28. August 2023 by updating OpenNDS to version 10.1.3.

An issue was discovered in OpenNDS Captive Portal before version 10.1.2. When the custom unescape callback is enabled, attackers can execute arbitrary OS commands by inserting them into the URL portion of HTTP GET requests. Affected OpenNDS Captive Portal before version 10.1.2 fixed in OpenWrt master, OpenWrt 23.05 and OpenWrt 22.03 on 28. August 2023 by updating OpenNDS to version 10.1.3.

An issue was discovered in OpenNDS before 10.1.2. It allows users to skip the splash page sequence (and directly authenticate) when it is using the default FAS key and OpenNDS is configured as FAS. Affected OpenNDS Captive Portal before version 10.1.2 fixed in OpenWrt master, OpenWrt 23.05 and OpenWrt 22.03 on 28. August 2023 by updating OpenNDS to version 10.1.3.

An issue was discovered in OpenNDS Captive Portal before version 10.1.2. It has a dobinauth NULL pointer dereference that be triggered with a crafted GET HTTP request with a missing User-Agent HTTP header. Triggering this issue results in crashing OpenNDS (a Denial-of-Service condition). The issue occurs when the client is about to be authenticated, and can be triggered only when the BinAuth option is set. Affected OpenNDS Captive Portal before version 10.1.2 fixed in OpenWrt master, OpenWrt 23.05 and OpenWrt 22.03 on 28. August 2023 by updating OpenNDS to version 10.1.3.