CVE-2026-85079 — Out-of-bounds write in Zigbee Simple_Desc_req handling
In EmberZNet 9.1.1 and earlier, a malformed Simple_Desc_req response can result in an out-of-bounds write potentially leading to remote code execution. This response must come from a device that has already joined the network, and the attacker must wait for a Simple_Desc_req before the attack can be performed.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.3% (30-day exploitation probability)+3
- Technical severity (critical)+10
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
CISA SSVC assessment CISA
Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
- Documented patch — github.com (NIST National Vulnerability Database)
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Silabs Emberznet, Silicon Labs EmberZNet).
- The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
- Apply the fixed version or the patch documented under Remediation.
- Search available logs for exploit probes matching the vulnerability class (memory corruption), errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Silabs | Emberznet | ≤ 9.1.1 | Vulnerable | NIST National Vulnerability Database |
| Silicon Labs | EmberZNet | ≤ 9.1.1 | Vulnerable | CVE Program (cve.org) e CISA ADP |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 7.5 | CVSS 4.0 | High | — | — | product-security@silabs.com via NIST National Vulnerability Database |
| 7.5 | CVSS 4.0 | High | — | — | Silabs via CVE Program (cve.org) e CISA ADP |
| 9.8 | CVSS 3.1 | Critical | 3.9 | 5.9 | nvd@nist.gov via NIST National Vulnerability Database |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H (score shown at the top: nvd@nist.gov) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
EPSS over time FIRST
Oct 23, 2026 → Oct 28, 2026 · 6 reading(s) · max 0.31%
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
- Correlate service crashes/restarts with inbound traffic; repeated crashes may indicate attempts.
Timeline
What happened to this CVE, newest first.
- 2026
- Fix documented
- Affected products added · silabs/emberznet
- CVSS changed · 7.5 → 9.8
- Source status changed · Undergoing Analysis → Analyzed
- Source status changed · Awaiting Analysis → Undergoing Analysis
- SSVC assessment updated
- Source status changed · Received → Awaiting Analysis
- Affected products added · silicon labs/emberznet
- Record published
- CVSS changed · 7.5
- Source status changed · → Received
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 2× References added · Oct 22, 2026 – Oct 29, 2026
- 1× Official description updated · Oct 22, 2026 – Oct 22, 2026
References
3 on the record
Elsewhere on this site
Related CVEs (same products)
- Critical CVE-2026-85080 Authenticated Denial-of-Service in Zigbee GetGroupMembership Handling 7d
- Critical CVE-2026-94502 Out-of-bounds write in Zigbee Publish Price Matrix handling 7d
- High CVE-2026-66282 Authenticated Denial-of-Service in Zigbee Publish Billing Period 7d
- High CVE-2026-66281 Authenticated Denial-of-Service in Zigbee Discover Attributes Handling 7d
- Medium CVE-2026-6432 Improper bounds validation in EmberZNet SDK Jun 25, 2026
- Medium CVE-2026-4526 Global ZCL command parser missing minimum-length validation in EmberZNet v9.0.2 Jun 25, 2026
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2026-85079 is "Out-of-bounds write in Zigbee Simple_Desc_req handling", rated Critical. It affects Emberznet (Silabs); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 9.8 describes technical severity. EPSS 0.31% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
Comments
Moderated technical discussion. Read the community guidelines.
No comments yet.
Sign in or create an account to comment and suggest corrections.