Vulnerability · Published Nov 26, 2025 · Assigned by VulnCheck
CVE-2020-36872BACnet Test Server 1.01 Malformed BVLC Length DoS
High 8.7
In plain English
A high-severity uncontrolled resource consumption in BACnet Test Server from BACnet Interoperability Test Services, Inc.. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 45% of all known vulnerabilities).
Official description
BACnet Test Server versions up to and including 1.01 contains a remote denial of service vulnerability in its BACnet/IP BVLC packet handling. The server fails to properly validate the BVLC Length field in incoming UDP BVLC frames on the default BACnet port (47808/udp). A remote unauthenticated attacker can send a malformed BVLC Length value to trigger an access violation and crash the application, resulting in a denial of service.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| BACnet Interoperability Test Services, Inc. | BACnet Test Server | 0 – through 1.01 |
Weakness: CWE-400 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
References
- https://www.zeroscience.mk/en/vulnerabilities/ZSL-2020-5597.php technical-description, exploit
- https://www.exploit-db.com/exploits/48860 exploit
- https://packetstormsecurity.com/files/159504 exploit
- https://cxsecurity.com/issue/WLB-2020100045 exploit
- https://www.bac-test.com/ product
- https://www.vulncheck.com/advisories/bacnet-test-server-malformed-bvlc-length-dos third-party-advisory