CVE-2026-51600
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.
What this means
- Exposure
- Exploitable remotely over the network, without authentication and with no action from the victim.
- Impact
- An attacker can take the service offline.
- Weakness
- A request that is cheap for the attacker consumes unbounded resources on the server.
- Likelihood
- Its EPSS score stays low: nothing points to imminent exploitation, which is no reason to leave it unpatched.
What to doFold into the next patch cycle. Start with the instances exposed to the internet.
Read automatically from the CVSS vector, the weakness type (CWE) and the EPSS score. The technical description above remains the one published by NIST.