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CVE-2026-62976 BACnet Stack: Consecutive AtomicWriteFile(record-access) appends can trigger a heap out-of-bounds read in the RAMFS file backend

8.7 high

High (8.7) in bacnet-stack bacnet-stack.

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BACnet Stack is a BACnet open source protocol stack C library for embedded systems. Prior to version 1.5.1, the RAMFS-backed FILE object implementation stores appended records as NUL-terminated strings, but its record-counting logic later walks the buffer as if an additional terminating empty record were present. As a result, two consecutive AtomicWriteFile(record-access) append requests can cause record_count() to call bacnet_strnlen() on a pointer that is already one byte past the end of the heap allocation. This issue has been patched in versions 1.5.1 and 1.6.0.

Severity

CVSS 4.0

8.7 high
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
CWE
CWE-125 Out-of-bounds Read
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.

ProductAffected
bacnet-stack< 1.5.1

Attack patterns (CAPEC)

  • CAPEC-540 Overread Buffers Likelihood: Low · Severity: High

The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits.

References

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