CVE-2026-6924Network attack vector

Secret prediction via deterministic DRBG seeding

Published Jul 23, 2026 · Updated Jul 23, 2026

Predictable randomness in Silicon Labs Matter version 0 allows remote attackers to infer secrets generated by SiWx917 devices. The SiWx917 entropy initialization gives the DRBG a predictable seed, causing all Matter code to reuse the same pseudorandom number stream. Network access requires no authentication or user interaction, and successful prediction exposes values whose secrecy depends on that stream.

CVSS severity8.7
High
EPSS probability0.45%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Predictable randomness in Silicon Labs Matter version 0 allows remote attackers to infer secrets generated by SiWx917 devices. The SiWx917 entropy initialization gives the DRBG a predictable seed, causing all Matter code to reuse the same pseudorandom number stream. Network access requires no authentication or user interaction, and successful prediction exposes values whose secrecy depends on that stream.

The record

CVE
CVE-2026-6924
Published
Jul 23, 2026
Updated
Jul 23, 2026
Vendor
Sigma Designs
Product
Silicon Labs Matter
Classifications
CWE-336
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 23, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 23, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Sigma Designs · Silicon Labs Matterversion=0

Published CVSS scores

8.7Silicon LabsCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-336Same Seed in Pseudo-Random Number Generator (PRNG)

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo