CVE
BACnet Stack: Stack-based buffer overflow in Notification Class RemoveListElement recipient-list decoding
- Exploited
- No known exploitation
- Fix
- Fixed in 1.4.4, 1.5.1, 1.6.0
- Who is exposed
- Not reported
Do first: Upgrade to a fixed version: 1.4.4, 1.5.1, 1.6.0.
- Published
- Last modified
- Whether it needs action now or is a reference record, by fixed rules, with why. Last checked is when cve.now last re-read it.What do these mean? →
- Reference
- Last checked
- A 0-100 score for how much a CVE matters across the industry: exploitation, exposure, how widely the software is used, severity and whether a fix exists.What do these mean? →
- 25/100 · provisional
- How many real-world setups can hit the bug, from the vendor's advisory and CISA data. It does not know your setup.What do these mean? →
- Unclear
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
BACnet Stack, a BACnet protocol library for embedded systems, contains a stack-based buffer overflow in how it handles RemoveListElement requests for the Notification-Class recipient list. An attacker can reach it remotely over the network without logging in by sending a request with more than the allowed number of recipient entries, which can write past the end of a stack buffer.
Written by anthropic/claude-haiku-5.5 from the sources below. Verify against them.
Read the original description
BACnet Stack is a BACnet open source protocol stack C library for embedded systems. Prior to versions 1.4.4, 1.5.1, and 1.6.0, a RemoveListElement request targeting Notification-Class.recipient-list can trigger a stack-based out-of-bounds write in the current master branch when the request contains more than NC_MAX_RECIPIENTS valid BACnetDestination elements. This issue has been patched in versions 1.4.4, 1.5.1, and 1.6.0.
Who should check
Teams running bacnet-stack master or releases up to 1.6.0-rc1 in embedded BACnet devices that use Notification Class objects with intrinsic reporting.
Read the source excerpt
“can trigger a stack-based out-of-bounds write in the current master branch”
cve.now Index
- Exploitation?/40Unknown. No CISA SSVC exploitation rating yet
- Exposure17/25No login or user action needed, reachable over the network without a login · Unknown: Advisories don't say whether default setups are affected
- Reach?/20Unknown. No tracked technology or package matched
- Severity8.2/10CVSS 8.2
- No patch0/5No signal
What would change the score
- Would score about 70 if added to CISA KEV
- Would score about 65 if CISA's SSVC rates exploitation active
- Would score about 30 if advisories confirm default setups are exposed
What to do
Upgrade to a fixed version: 1.4.4, 1.5.1, 1.6.0.
Check your systems with an agent
Paste this into a coding or ops agent. It checks your systems read-only and reports a table per asset.
Check whether my systems are affected by CVE-2026-47259 (BACnet Stack: Stack-based buffer overflow in Notification Class RemoveListElement recipient-list decoding), using the cve.now data below.
Rules: work read-only. Do not run exploit code, proof-of-concept scripts or scanners that send attack payloads, and do not change any configuration, package, image or deployment. Report findings only.
What cve.now has for CVE-2026-47259 (entry last updated 2026-11-12):
Affected:
- bacnet-stack bacnet-stack: fixed in 1.4.4; fixed in 1.5.1; fixed in 1.6.0
Fixed versions: 1.4.4, 1.5.1, 1.6.0.
Conditions (all must be true for the bug to be hit):
- A RemoveListElement request targets the Notification-Class recipient-list property. (source: https://github.com/bacnet-stack/bacnet-stack/security/advisories/GHSA-9w9m-w7w5-rrv3)
- The request contains more than NC_MAX_RECIPIENTS valid BACnetDestination elements (10 by default). (source: https://github.com/bacnet-stack/bacnet-stack/security/advisories/GHSA-9w9m-w7w5-rrv3)
- Affects the current master branch, with affected versions up to 1.6.0-rc1. (source: https://github.com/bacnet-stack/bacnet-stack/security/advisories/GHSA-9w9m-w7w5-rrv3)
Setup: unknown whether the bug needs a non-default feature or setting. Check the advisory.
Attacker needs: network access, no login, no user action.
CISA KEV: CVE-2026-47259 is not listed as of cve.now's last read.
This KEV status is for CVE-2026-47259 only. If you also check another CVE, look up its own KEV status; never assume it from this one.
How to check:
- Installed software: check what is actually running, not what a repo declares. Read the version from each host, container image and Kubernetes node (the binary's version output, the OS package database, image layers), and check whether the conditions above hold there. Distribution packages may carry a backported fix under an older version number; confirm against the distribution's own advisory.
Verify against the linked advisories before concluding, and cite the date you read each one:
- https://github.com/bacnet-stack/bacnet-stack/security/advisories/GHSA-9w9m-w7w5-rrv3
- https://github.com/bacnet-stack/bacnet-stack/pull/1353
Do not conclude an asset is unaffected unless you checked it and the evidence covers both its version and the conditions above. If you could not check something, mark it unknown and say what is missing.
Report a table with one row per asset and these columns: Asset | Version or build | Status (affected, fixed, not applicable, unknown) | Compensating controls | Exposure (internet-facing, internal, none) | Evidence | Next action.
Entry: https://cve.now/CVE-2026-47259
For follow-up questions, use the cve.now MCP server at https://mcp.cve.now/mcp (no authentication), for example execute with name cve.get and arguments {"id": "CVE-2026-47259"}.Timeline
- CVE published
- First seen by cve.now
Affected versions
- bacnet-stack bacnet-stack
fixed in 1.4.4; fixed in 1.5.1; fixed in 1.6.0
Evidence 4
Vendor advisory · 1
Establishes: Affected and fixed versions.
- Advisory
CVE record · 2
Establishes: The identifier and description.
- Record
- Record
Other links · 1
- Repository
Corrections
None so far.
Something wrong on this page? Report an error. Every fix is listed here.
Questions about CVE-2026-47259
Is CVE-2026-47259 being exploited?
It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.Source: cve.now feed data
What does this mean?
A crafted RemoveListElement request that targets the Notification-Class recipient list with too many entries causes a stack-based out-of-bounds write. The write can crash the BACnet device, which is a denial of service.Source: github.com
Which versions are affected by CVE-2026-47259?
bacnet-stack: before 1.4.4; before 1.5.1; before 1.6.0.Source: cve.now feed data
Am I affected, and how do I check?
The bug is in the current master branch, with affected versions up to 1.6.0-rc1. It needs a request with more than NC_MAX_RECIPIENTS valid BACnetDestination elements, which is 10 by default. Check the bacnet-stack version and the NC_MAX_RECIPIENTS setting in the build.Source: github.com
How do I fix CVE-2026-47259?
Upgrade to 1.4.4, 1.5.1, or 1.6.0, which are the fixed versions listed for this vulnerability.Source: github.com