BACnet Test Server 1.01 Malformed BVLC Length DoS
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- No fix listed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-400.
Summary
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.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| BACnet Interoperability Test Services, Inc. | BACnet Test Server | up to 1.01 | — | No fix listed | CNA |
- BACnet Test Server VendorBACnet Interoperability Test Services, Inc. Affected up to 1.01 Fixed in — No fix listed CNA
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2020-36872
- 2026-10-03 Alias added: GHSA-3v4j-cjvq-5p59
References
Sources
- CVE-2020-36872 · CVE Program
- CVE-2020-36872 · NVD
- FIRST EPSS
- GHSA-3v4j-cjvq-5p59 · GitHub Advisory Database · CC BY 4.0
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