CVE-2026-97692BACnet Stack: pre-auth out-of-bounds read that escalates to an out-of-bounds write into global memory
- 7.7HighCVSS base score
- 0.50%Exploitation in 30 daysEPSS · top 57% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
BACnet Stack is a BACnet open source protocol stack C library for embedded systems. Prior to versions 1.4.6, 1.5.2, and 1.6.1, the BACnet/SC message decoder walks the header-option list by following each option's MORE bit. Nothing rejects a list whose last option still has the MORE bit set, and the decode walk has no upper bound on how many options it processes. A single crafted BVLC-SC frame makes the walk advance one option past the end of the message and read message[message_len], one byte out of bounds. When the bytes after the message carry more MORE-set option markers, the walk keeps going: it runs past the fixed 4-entry option array and writes decoded option fields out of bounds. On the server that decode array is the static global bsc_dm, so the out-of-bounds write lands in adjacent BSS. Both faults are reachable before authentication, from the first frame a peer sends on a BACnet/SC connection, and the bytes that follow the message are the same peer's prior-frame data. This issue has been patched in versions 1.4.6, 1.5.2, 1.6.1, and 1.7.0.
Timeline
ID reserved
By GitHub_M
- 50 days later
· 50 days later
Published
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | High7.7 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:H/A:H |
| NVDNVD · Awaiting Analysis | 3.1 | High7.7 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.50% · top 57% of all CVEs (14 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.7.
Affected products
- affected < 1.4.6
- affected >= 1.5.0, < 1.5.2
- affected >= 1.6.0, < 1.6.1
References
References2
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-125696 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-97692)Record last updated .