CVE-2026-21878

HIGH

7.5

Description

BACnet Stack is a BACnet open source protocol stack C library for embedded systems. Prior to 1.5.0.rc3, a vulnerability has been discovered in BACnet Stack's file writing functionality where there is no validation of user-provided file paths, allowing attackers to write files to arbitrary directories. This affects apps/readfile/main.c and ports/posix/bacfile-posix.c. This vulnerability is fixed in 1.5.0.rc3.

CVE Details

CVSS v3.1 Score7.5

SeverityHIGH

CVSS VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Attack VectorNETWORK

ComplexityLOW

Privileges RequiredNONE

User InteractionNONE

Published2/13/2026

Last Modified2/18/2026

Sourcenvd

Honeypot Sightings0

Affected Products

bacnetstack:bacnet_stack

Weaknesses (CWE)

CWE-22

References

https://github.com/bacnet-stack/bacnet-stack/commit/c5dc00a77b4bc2550befa67a930b333e299c18f3(security-advisories@github.com)

https://github.com/bacnet-stack/bacnet-stack/security/advisories/GHSA-p8rx-c26w-545j(security-advisories@github.com)

IOC Correlations

No correlations recorded

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