CVE-2026-21878

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.
Configurations

Configuration 1 (hide)

OR cpe:2.3:a:bacnetstack:bacnet_stack:1.5.0:rc1:*:*:*:*:*:*
cpe:2.3:a:bacnetstack:bacnet_stack:1.5.0:rc2:*:*:*:*:*:*

History

17 Jun 2026, 10:19

Type Values Removed Values Added
Summary
  • (es) BACnet Stack es una librería C de pila de protocolos BACnet de código abierto para sistemas embebidos. Antes de la versión 1.5.0.rc3, se ha descubierto una vulnerabilidad en la funcionalidad de escritura de archivos de BACnet Stack donde no hay validación de las rutas de archivo proporcionadas por el usuario, lo que permite a los atacantes escribir archivos en directorios arbitrarios. Esto afecta a apps/readfile/main.c y ports/posix/bacfile-posix.c. Esta vulnerabilidad está corregida en la versión 1.5.0.rc3.
References () https://github.com/bacnet-stack/bacnet-stack/security/advisories/GHSA-p8rx-c26w-545j - Vendor Advisory, Exploit () https://github.com/bacnet-stack/bacnet-stack/security/advisories/GHSA-p8rx-c26w-545j - Exploit, Vendor Advisory

18 Feb 2026, 18:49

Type Values Removed Values Added
CPE cpe:2.3:a:bacnetstack:bacnet_stack:1.5.0:rc1:*:*:*:*:*:*
cpe:2.3:a:bacnetstack:bacnet_stack:1.5.0:rc2:*:*:*:*:*:*
References () https://github.com/bacnet-stack/bacnet-stack/commit/c5dc00a77b4bc2550befa67a930b333e299c18f3 - () https://github.com/bacnet-stack/bacnet-stack/commit/c5dc00a77b4bc2550befa67a930b333e299c18f3 - Patch
References () https://github.com/bacnet-stack/bacnet-stack/security/advisories/GHSA-p8rx-c26w-545j - () https://github.com/bacnet-stack/bacnet-stack/security/advisories/GHSA-p8rx-c26w-545j - Vendor Advisory, Exploit
First Time Bacnetstack bacnet Stack
Bacnetstack

13 Feb 2026, 19:17

Type Values Removed Values Added
New CVE

Information

Published : 2026-02-13 19:17

Updated : 2026-06-17 10:19


NVD link : CVE-2026-21878

Mitre link : CVE-2026-21878

CVE.ORG link : CVE-2026-21878


JSON object : View

Products Affected

bacnetstack

  • bacnet_stack
CWE
CWE-22

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')