CVE-2026-21878
Last modified
CVE-2026-21878 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. 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. EPSS estimates a 0.36% chance of exploitation in the next 30 days.
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
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Weakness Enumeration
Affected Software
| Vendor | Product | Versions | Update |
|---|---|---|---|
| Bacnetstack | Bacnet Stack | 1.5.0 | Rc1 |
References
Timeline
- Published
- Last Modified
- Status
- Analyzed
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