CVE-2025-11423 Overview
A memory corruption vulnerability has been identified in Tenda CH22 firmware version 1.0.0.1. This vulnerability affects the formSafeEmailFilter function located in the /goform/SafeEmailFilter file. By manipulating the page argument, an attacker can trigger memory corruption, potentially leading to device compromise or denial of service conditions.
Critical Impact
This network-accessible vulnerability allows remote attackers to corrupt memory on affected Tenda CH22 devices without authentication, potentially leading to arbitrary code execution or device instability.
Affected Products
- Tenda CH22 Firmware version 1.0.0.1
- Tenda CH22 hardware devices running vulnerable firmware
Discovery Timeline
- October 8, 2025 - CVE-2025-11423 published to NVD
- February 24, 2026 - Last updated in NVD database
Technical Details for CVE-2025-11423
Vulnerability Analysis
This vulnerability is classified under CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer). The formSafeEmailFilter function fails to properly validate or sanitize the page argument before processing it, resulting in operations that write or read beyond the intended memory boundaries.
The vulnerability exists in the web management interface of the Tenda CH22 router, which is typically accessible over the network. The affected endpoint /goform/SafeEmailFilter processes user-supplied input without adequate bounds checking, creating an exploitable memory corruption condition.
Root Cause
The root cause stems from improper input validation within the formSafeEmailFilter function. When the page parameter is processed, the function does not enforce proper boundary restrictions on memory operations. This allows an attacker to supply malformed input that causes the application to write data outside allocated memory regions, corrupting adjacent memory structures.
Embedded device firmware often lacks modern memory protection mechanisms, making such buffer management flaws particularly dangerous. The Tenda CH22's web interface appears to directly process HTTP parameters without sanitization layers.
Attack Vector
The attack can be executed remotely over the network without requiring authentication. An attacker sends a crafted HTTP request to the /goform/SafeEmailFilter endpoint with a maliciously constructed page parameter value. This triggers the memory corruption condition in the formSafeEmailFilter function.
The vulnerability mechanism involves improper handling of the page argument in the email filter configuration handler. When processing this parameter, the firmware fails to validate input length and format, leading to memory corruption. Detailed technical information is available in the GitHub Issue Discussion and VulDB entry #327358.
Detection Methods for CVE-2025-11423
Indicators of Compromise
- Unexpected HTTP POST requests targeting /goform/SafeEmailFilter with anomalous page parameter values
- Device crashes, reboots, or unresponsive behavior following web interface access
- Unusual memory usage patterns or process termination in device logs
- Modified device configurations without administrative action
Detection Strategies
- Monitor network traffic for HTTP requests to /goform/SafeEmailFilter containing oversized or malformed page parameters
- Implement intrusion detection rules to flag suspicious requests to Tenda router management interfaces
- Deploy network-based anomaly detection to identify exploitation attempts targeting embedded devices
- Review device logs for unexpected service restarts or memory-related errors
Monitoring Recommendations
- Enable logging on network perimeter devices to capture traffic to Tenda device management interfaces
- Segment IoT and network infrastructure devices from user networks to limit exposure
- Regularly audit network devices for unusual configuration changes or behavioral anomalies
How to Mitigate CVE-2025-11423
Immediate Actions Required
- Restrict network access to the Tenda CH22 web management interface to trusted IP addresses only
- Disable remote administration if not required for operations
- Place affected devices behind a firewall with strict access control rules
- Monitor for firmware updates from Tenda and apply immediately when available
Patch Information
At the time of publication, no official patch has been released by Tenda for this vulnerability. Organizations should monitor the Tenda Official Website for security updates and firmware releases addressing CVE-2025-11423.
Workarounds
- Implement network segmentation to isolate affected Tenda CH22 devices from untrusted networks
- Configure access control lists (ACLs) to restrict management interface access to specific administrator IP addresses
- Consider replacing vulnerable devices with alternatives that receive regular security updates
- Use a VPN for any necessary remote administration to add an authentication layer
# Example: Restrict access to router management interface via iptables
# Block external access to Tenda management port (adjust port as needed)
iptables -A INPUT -p tcp --dport 80 -s 192.168.1.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -j DROP
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
