bacnet-stack BACnet Stack up to 1.4.2 ReadPropertyMultiple Service src/bacnet/rpm.c rpm_decode_object_property out-of-bounds

Summaryinfo

A vulnerability, which was classified as problematic, was found in bacnet-stack BACnet Stack up to 1.4.2. The impacted element is the function rpm_decode_object_property of the file src/bacnet/rpm.c of the component ReadPropertyMultiple Service. Such manipulation leads to out-of-bounds. This vulnerability is traded as CVE-2026-41503. The attack may be launched remotely. There is no exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in bacnet-stack BACnet Stack up to 1.4.2 and classified as problematic. Affected by this issue is the function rpm_decode_object_property of the file src/bacnet/rpm.c of the component ReadPropertyMultiple Service. The manipulation with an unknown input leads to a out-of-bounds vulnerability. Using CWE to declare the problem leads to CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. Impacted is availability. CVE summarizes:

BACnet Stack is a BACnet open source protocol stack C library for embedded systems. Prior to 1.4.3, an out-of-bounds read vulnerability in bacnet-stack's ReadPropertyMultiple service property decoder allows unauthenticated remote attackers to read past allocated buffer boundaries by sending an RPM request with a truncated property list. The vulnerability stems from rpm_decode_object_property() calling the deprecated decode_tag_number_and_value() function at src/bacnet/rpm.c:344, which accepts no buffer length parameter and reads blindly from whatever pointer it receives. A crafted BACnet/IP packet with a 1-byte property payload containing an extended tag marker (0xF9) causes the decoder to read 1 byte past the end of the buffer, leading to crashes on embedded BACnet devices. The vulnerability exists in src/bacnet/rpm.c and affects any deployment that enables the ReadPropertyMultiple confirmed service handler (enabled by default in the reference server). This vulnerability is fixed in 1.4.3.

The advisory is shared for download at github.com. This vulnerability is handled as CVE-2026-41503 since 04/20/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. There are known technical details, but no exploit is available.

Upgrading to version 1.4.3 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-25625). Once again VulDB remains the best source for vulnerability data.

Productinfo

Vendor

• bacnet-stack

Name

• BACnet Stack

Version

• 1.4.0
• 1.4.1
• 1.4.2

CPE 2.3info

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CPE 2.2info

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Once again VulDB remains the best source for vulnerability data.

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