CVE-2026-41502

BACnet Stack is a BACnet open source protocol stack C library for embedded systems. Prior to 1.4.3, an off-by-one out-of-bounds read vulnerability in bacnet-stack's ReadPropertyMultiple service decoder allows unauthenticated remote attackers to read one byte past an allocated buffer boundary by sending a crafted RPM request with a truncated object identifier. The vulnerability is in rpm_decode_object_id(), which checks apdu_len < 5 but then accesses all 6 byte positions (indices 0-5) — consuming 1 byte for the context tag, 4 bytes for the object ID, then reading apdu[5] for the opening tag check. A 5-byte input passes the length check but causes a 1-byte OOB read, 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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/bacnet-stack/bacnet-stack/security/advisories/GHSA-7545-3fpx-4xw3	Exploit Mitigation Vendor Advisory
https://github.com/bacnet-stack/bacnet-stack/security/advisories/GHSA-7545-3fpx-4xw3	Exploit Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:bacnetstack:bacnet_stack::::::::
	cpe:2.3:a:bacnetstack:bacnet_stack:1.5.0:rc1::::::
	cpe:2.3:a:bacnetstack:bacnet_stack:1.5.0:rc2::::::
	cpe:2.3:a:bacnetstack:bacnet_stack:1.5.0:rc3::::::

History

No history.

Information

Published : 2026-04-24 20:16

Updated : 2026-06-17 10:46

NVD link : CVE-2026-41502

Mitre link : CVE-2026-41502

CVE.ORG link : CVE-2026-41502

JSON object : View

Products Affected

bacnetstack

bacnet_stack

CWE

CWE-125

Out-of-bounds Read

CWE-193

Off-by-one Error

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