Buffer overflow in N/a
CVE-2026-51603
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 second SETUP request. After completing the OPTIONS, DESCRIBE, and a legitimate first SETUP request to obtain a valid session ID, the RTSP service's second-stage URL routing parser fails to validate the length of the URL field in the subsequent SETUP request. By supplying a URL consisting of exactly four consecutive repetitions of a valid RTSP URL, an attacker can bypass first-stage format validation and trigger a stack buffer overflow, causing an immediate crash of the RTSP service process and rendering the device inaccessible to all clients on the local network.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.006 (44.8th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 45th percentile — 44.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: 0.000
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2026-51603?
- CVE-2026-51603 is a high-severity vulnerability in N/a, classified under Stack-based Buffer Overflow. CVSS score: 7.5/10. Published 2026-07-09.
- How severe is CVE-2026-51603?
- High severity. CVSS v3 base score is 7.5 out of 10.