CVE-2026-26264 (GCVE-0-2026-26264)
Vulnerability from cvelistv5 – Published: 2026-02-13 18:14 – Updated: 2026-02-13 18:50
VLAI
EPSS
VEX
Title
BACnet Stack WriteProperty decoding length underflow leads to OOB read and crash
Summary
BACnet Stack is a BACnet open source protocol stack C library for embedded systems. Prior to 1.5.0rc4 and 1.4.3rc2, a malformed WriteProperty request can trigger a length underflow in the BACnet stack, leading to an out‑of‑bounds read and a crash (DoS). The issue is in wp.c within wp_decode_service_request. When decoding the optional priority context tag, the code passes apdu_len - apdu_size to bacnet_unsigned_context_decode without validating that apdu_size <= apdu_len. If a truncated APDU reaches this path, apdu_len - apdu_size underflows, resulting in a large size being used for decoding and an out‑of‑bounds read. This vulnerability is fixed in 1.5.0rc4 and 1.4.3rc2.
Severity
SSVC
Exploitation: poc
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-02-13 18:49 UTC
CWE
- CWE-125 - Out-of-bounds Read
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/bacnet-stack/bacnet-stack/secu… | x_refsource_CONFIRM |
| https://github.com/bacnet-stack/bacnet-stack/comm… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| bacnet-stack | bacnet-stack |
Affected:
>= 1.5.0rc1, < 1.5.0rc4
Affected: < 1.4.3rc2 |
guessed |
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