CVSS 3.1
7.1 highCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:HCVE-2026-52786 BACnet Stack: malicious ReadPropertyMultiple-ACK with excessive properties causes global-buffer-overflow in ProcessRPMData()
High (7.1) in bacnet-stack bacnet-stack. EPSS 0.2% estimated probability of exploitation activity in the next 30 days.
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BACnet Stack is a BACnet open source protocol stack C library for embedded systems. Prior to versions 1.4.5, 1.5.1, and 1.6.0, in the official apps/epics client tool on v1.6.0-rc1 (not in the generic BACnet RPM ACK decoder alone) a malicious BACnet/IP endpoint can reply to the EPICS tool’s legitimate ReadPropertyMultiple request with a syntactically valid ReadPropertyMultiple-ACK that contains more heading properties than the tool’s fixed local storage can hold. The response is decoded successfully and later consumed by ProcessRPMData(), which writes property values into a fixed global array using an unbounded linear index. This results in a reproducible global-buffer-overflow in apps/epics/main.c. This is a network-reachable memory corruption in the official epics tool’s response-processing path. The root cause is that apps/epics treats a remotely supplied variable-length RPM property list as if it were a trusted, fixed-size local heading-property set. This issue has been patched in versions 1.4.5, 1.5.1, and 1.6.0.
Severity
- EPSS
- 0.2% estimated probability of exploitation activity in the next 30 days; 13th percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
- OWASP Top 10
- A05:2025 Injection
- Published
- Modified
- Assigned by
- GitHub_M (CNA)
- NVD analysis
- Awaiting analysis
- Record from
- the NVD, synced
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Affected
Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| bacnet-stack | < 1.4.5 |
| bacnet-stack | < 1.5.1 |
| bacnet-stack | < 1.6.0 |
Attack patterns (CAPEC)
- CAPEC-100 Overflow Buffers Likelihood: High · Severity: Very High
The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits.