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CVE-2026-21878 Detail

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.


Metrics

NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/bacnet-stack/bacnet-stack/commit/c5dc00a77b4bc2550befa67a930b333e299c18f3 GitHub, Inc.
https://github.com/bacnet-stack/bacnet-stack/security/advisories/GHSA-p8rx-c26w-545j GitHub, Inc.

Weakness Enumeration

CWE-ID CWE Name Source
CWE-22 Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') GitHub, Inc.  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-21878
NVD Published Date:
02/13/2026
NVD Last Modified:
02/13/2026
Source:
GitHub, Inc.