CVE-2025-2957 Overview
CVE-2025-2957 affects TRENDnet TEW-411BRP+ version 2.07, a wireless broadband router. The vulnerability resides in the sub_401DB0 function within /usr/sbin/httpd, the device's HTTP request handler. Attackers on the adjacent network can trigger a null pointer dereference by sending crafted HTTP requests. Successful exploitation causes the service to crash, resulting in denial of service against the router's management interface. The weakness is classified under [CWE-404: Improper Resource Shutdown or Release]. The exploit has been publicly disclosed. According to the disclosure, the vendor was contacted but did not respond.
Critical Impact
Adjacent-network attackers can crash the embedded HTTP daemon on affected TRENDnet TEW-411BRP+ routers, disrupting device administration and network management functions.
Affected Products
- TRENDnet TEW-411BRP+ wireless router
- Firmware version 2.07
- Embedded httpd binary at /usr/sbin/httpd
Discovery Timeline
- 2025-03-30 - CVE-2025-2957 published to the National Vulnerability Database
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-2957
Vulnerability Analysis
The flaw is a null pointer dereference inside the sub_401DB0 function of the router's httpd binary. The function processes incoming HTTP requests but fails to validate that a required pointer is non-null before dereferencing it. When an attacker submits a specially crafted request, the daemon reads from or writes to a null address and terminates. Because httpd serves the router's web administration interface, its crash removes the primary configuration channel. The CWE-404 classification reflects the improper handling of the resource lifecycle during request processing. The vulnerability's EPSS probability is approximately 0.389%.
Root Cause
The root cause is missing input validation inside sub_401DB0. The function assumes that pointers derived from parsed HTTP request fields are always valid. When parsing fails or when an expected header or parameter is absent, the function proceeds to dereference an uninitialized or null pointer. Embedded routers frequently ship with minimal defensive coding in their custom HTTP stacks, and TEW-411BRP+ firmware 2.07 reflects this pattern.
Attack Vector
Exploitation requires network adjacency, meaning the attacker must reside on the same local network segment as the router, such as a Wi-Fi client or wired LAN peer. No authentication or user interaction is required. The attacker sends a malformed HTTP request to the router's management port, triggering the dereference and crashing the daemon. Repeated requests sustain the outage. Public disclosure of the exploit lowers the barrier for opportunistic abuse on untrusted LAN segments.
No verified exploit code is published in the enriched data. See the VulDB entry #302010 and the VulDB CTI reference for additional technical context.
Detection Methods for CVE-2025-2957
Indicators of Compromise
- Unexpected restarts or unavailability of the router's web administration interface on affected TEW-411BRP+ devices
- HTTP requests to the router from LAN hosts containing malformed headers, truncated fields, or unusual parameter combinations
- Repeated TCP resets or connection failures to the router's HTTP management port originating from a single internal host
Detection Strategies
- Capture LAN traffic directed at the router's management interface and inspect for malformed HTTP requests targeting /usr/sbin/httpd endpoints
- Monitor router uptime and httpd process availability through SNMP or scheduled HTTP probes to detect service crashes
- Correlate device management outages with recent HTTP request patterns from internal hosts
Monitoring Recommendations
- Alert when the router's web interface becomes unreachable from a trusted management host while ICMP responses continue
- Baseline the volume and shape of HTTP requests sent to internal network devices and flag deviations from typical administrative traffic
- Log DHCP leases and ARP activity to identify unknown devices on segments that can reach vulnerable routers
How to Mitigate CVE-2025-2957
Immediate Actions Required
- Restrict access to the router's web administration interface to a dedicated management VLAN or specific trusted IP addresses
- Disable remote and wireless administration on the TEW-411BRP+ where operationally feasible
- Inventory TRENDnet TEW-411BRP+ devices on firmware 2.07 and plan replacement, since the vendor did not respond to disclosure
Patch Information
No vendor patch is available. The disclosure notes that TRENDnet was contacted but did not respond. Because TEW-411BRP+ is a legacy consumer router, administrators should assume no fix will be issued and prioritize replacement with a supported model that receives active firmware maintenance.
Workarounds
- Place the router behind a network segmentation boundary that blocks untrusted LAN hosts from reaching its HTTP management port
- Enforce MAC filtering and WPA2 or WPA3 authentication on Wi-Fi to limit which clients become adjacent-network attackers
- Monitor the device's availability and automatically power-cycle the router if the HTTP service becomes unresponsive as a short-term operational control
- Replace end-of-life hardware with a currently supported router model as the long-term remediation
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
