Review reviewHigh

CVE-2026-51600

the affected product

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.

CVSS
7.5
EPSS
0.40%
33.1% percentile
CISA KEV
Not listed
Published
2026.07.10
PRIORITY ASSESSMENT

Review review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV
Exploit probability0.40%
Technical severityCVSS 7.5

Vulnerability overview

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.

Affected product and versions

Product
the affected product
Affected versions
See the vendor advisory and NVD configuration data
Fixed versions
No verified fixed-version field is available yet

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide
  1. 1
    Identify

    Confirm that the affected product and an affected version are present.

  2. 2
    Prioritize

    Combine exploitation signals with asset exposure and business criticality.

  3. 3
    Remediate

    Follow the vendor advisory or supported update path and preserve rollback options.

  4. 4
    Verify

    Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
CWE-400, CWE-703
CVE-2026-51600 — Vulnerability advisory | SECUFOCUS NOW