What is the CVSS score of CVE-2025-66624?

CVE-2025-66624 has a CVSS 3.1 base score of 7.5 (High). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. EPSS exploitation probability: 0.1%.

Which versions of Bacnet Stack are affected by CVE-2025-66624?

A critical vulnerability in BACnet Protocol Stack library (CVE-2025-66624) allows remote attackers to trigger denial-of-service attacks against systems using affected versions prior to 1.5.0.rc2.. A patch is available.

Is there a public PoC exploit available for CVE-2025-66624?

Yes, a public proof-of-concept exploit is available for CVE-2025-66624. Prioritise patching immediately. EPSS: 0.1%.

How to fix or mitigate CVE-2025-66624?

Within 24 hours: Identify all systems and applications using BACnet Protocol Stack library versions prior to 1.5.0.rc2; document inventory and assess business criticality. Within 7 days: Develop and test patch deployment plan in non-production environment; prioritize critical infrastructure and customer-facing systems. Within 30 days: Deploy vendor patch (v1.5.0.rc2 or later) across all affected systems; verify functionality post-patch and confirm vulnerability remediation through security scanning.

Bacnet Stack CVE-2025-66624

EUVD-2025-201496 HIGH

Out-of-bounds Read (CWE-125)

2025-12-05 security-advisories@github.com

Buffer Overflow Information Disclosure Bacnet Stack Bacnetstack

7.5

CVSS 3.1 · GitHub Advisory

Severity by source

GitHub Advisory PRIMARY

7.5 HIGH

AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Primary rating from GitHub Advisory · only source for this CVE.

CVSS VectorGitHub Advisory

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Lifecycle Timeline

EUVD ID Assigned

Mar 15, 2026 - 17:08 euvd

EUVD-2025-201496

Analysis Generated

Mar 15, 2026 - 17:08 vuln.today

Patch released

Mar 15, 2026 - 17:08 nvd

Patch available

PoC Detected

Feb 18, 2026 - 18:21 vuln.today

Public exploit code

CVE Published

Dec 05, 2025 - 19:15 nvd

HIGH 7.5

DescriptionGitHub Advisory

BACnet Protocol Stack library provides a BACnet application layer, network layer and media access (MAC) layer communications services. Prior to 1.5.0.rc2, The npdu_is_expected_reply function in src/bacnet/npdu.c indexes request_pdu[offset+2/3/5] and reply_pdu[offset+1/2/4] without verifying that those APDU bytes exist. bacnet_npdu_decode() can return offset == 2 for a 2-byte NPDU, so tiny PDUs pass the version check and then get read out of bounds. On ASan/MPU/strict builds this is an immediate crash (DoS). On unprotected builds it is undefined behavior and can mis-route replies; RCE is unlikely because only reads occur, but DoS is reliable.

Analysis

Technical ContextAI

An out-of-bounds memory access occurs when code reads from or writes to memory locations outside the intended buffer boundaries. This vulnerability is classified as Out-of-bounds Read (CWE-125).

RemediationAI

A vendor patch is available — apply it immediately. Implement proper bounds checking on all array and buffer accesses. Use memory-safe languages or static analysis tools to detect OOB issues.