CVE-2026-51600
HighCVSS 7.5Exploitation Probability (EPSS)
Low risk32th percentile - higher than 32% of all known CVEs
Summary
Tenda CP3 V3.0 firmware V31.1.9.91 fails to validate the Content-Length header in RTSP requests (DESCRIBE, SETUP, PLAY). When a request includes this header without a body, the RTSP parser enters a persistent body-awaiting state, permanently blocking the TCP connection. An unauthenticated remote attacker can exploit this to exhaust TCP resources and cause a denial-of-service condition.
Risk Assessment
The risk is a remote unauthenticated DoS attack that can render the device unavailable, potentially disrupting video surveillance operations.
Recommendation
Immediately update the Tenda CP3 V3.0 firmware to the latest version that fixes the Content-Length header validation. If no update is available, restrict access to RTSP ports (default 554) to trusted networks only.
Other vulnerabilities in Tenda CP3
See all- CVE-2026-86153Critical
A vulnerability has been found in Tenda CP3 (version 27.5.57.101) in the CRedirServer::SetRedirectEnable function of the Functions/Redirect.cpp file. The manipulation leads to improper privilege management. Remote exploitation is possible.
- CVE-2026-86152Critical
A flaw has been found in Tenda CP3 (version 27.5.57.101) in the CAutoAddWifi::ThreadProc function of the Functions/AutoAddWifi.cpp file in the Kylin component. Executing a manipulation can lead to OS command injection. The attack may be launched remotely.
- CVE-2026-86151Critical
A vulnerability was detected in Tenda CP3 (version 27.5.57.101) in the sub_2F77E8 function of the Apis/system.c file in the Network Configuration Management component. Performing a manipulation results in OS command injection. The attack may be initiated remotely.
- CVE-2026-86149Critical
A vulnerability has been identified in Tenda CP3 27.5.57.101 in the file Net/NetCheckPing.cpp. Manipulation of the interface_name/host arguments causes OS command injection. The attack can be initiated remotely.
- CVE-2026-86148Critical
A vulnerability has been discovered in Tenda CP3 27.5.57.101 in the SystemAsh function of the file Apis/system.c of the Kylin component. Manipulation of the AlarmVoiceURL argument results in OS command injection. The attack can be launched remotely.
- CVE-2026-86150Medium
A security vulnerability has been detected in Tenda CP3 27.5.57.101. Impacted is an unknown function of the file custom-x/softap/hostapd. Such manipulation of the argument wpa_passphrase leads to hard-coded credentials. The attack can be launched remotely. The exploit has been disclosed publicly and may be used.
- CVE-2026-51606High
An improper input handling vulnerability in the RTSP service of Tenda CP3 V3.0 (firmware V31.1.9.91) causes the device to abruptly terminate the TCP connection with a RST packet when a request containing an oversized field value is received, without returning any RFC 2326-compliant error response. This behavior affects the request-line URL field and header field values across multiple RTSP request types.
- CVE-2026-51605High
A stack-based buffer overflow vulnerability in the RTSP service of Tenda CP3 V3.0 (firmware V31.1.9.991) allows an unauthenticated remote attacker to cause a denial of service via a crafted TEARDOWN request.
- CVE-2026-51604High
A stack-based buffer overflow vulnerability in the RTSP service of Tenda CP3 V3.0 (firmware V31.1.9.91) allows an unauthenticated remote attacker to cause a denial of service via a crafted PLAY request.
- CVE-2026-51603High
A stack-based buffer overflow vulnerability exists in the RTSP service of Tenda CP3 V3.0 (firmware V31.1.9.91). An unauthenticated remote attacker can cause a denial of service by sending a crafted second SETUP request, crashing the RTSP service.
Original NVD description (English source)
Tenda CP3 V3.0 firmware V31.1.9.91 does not validate the Content-Length header field in RTSP requests (including DESCRIBE, SETUP, and PLAY methods). When a request carrying a Content-Length header is received without a corresponding message body, the RTSP parser enters a persistent body-awaiting state, causing the affected TCP connection to become permanently non-functional. The device does not actively close the connection, resulting in a TCP resource leak. This issue can be exploited by an unauthenticated remote attacker to cause a denial-of-service condition.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS