Bacnet · Bacnet Protocol Stack · CVE-2019-12480
**Name of the Vulnerable Software and Affected Versions**
BACnet Protocol Stack versions through 0.8.6
**Description**
The issue is related to a segmentation fault that leads to a denial of service in the BACnet APDU Layer. This occurs due to a malformed DCC in AtomicWriteFile, AtomicReadFile, and DeviceCommunicationControl services. An unauthenticated remote attacker can cause a denial of service, resulting in the bacserv daemon crash, because of an invalid read in bacdcode.c during the parsing of alarm tag numbers.
**Recommendations**
For BACnet Protocol Stack versions through 0.8.6, consider restricting access to the AtomicWriteFile, AtomicReadFile, and DeviceCommunicationControl services until a patch is available. As a temporary workaround, avoid using the `bacdcode.c` file for parsing alarm tag numbers until the issue is resolved. At the moment, there is no information about a newer version that contains a fix for this vulnerability.