Vulnerability-Lookup

CVE-2026-6924 (GCVE-0-2026-6924)

Vulnerability from cvelistv5 – Published: 2026-07-23 21:05 – Updated: 2026-07-24 13:40

Title

Weak entropy initialization in Silicon Labs Matter SiWx917 TinyCrypt path

Summary

A bug in the entropy initialization for SiWx917 causes the DRBG to use a predictable seed. As such, all random numbers generated in the Matter code use the same stream of numbers. This vulnerability was discovered after the impacted repository was already deprecated.

Severity

8.7 (High)


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

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator (v2.0.3)

CWE

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

Assigner

Silabs

References

2 references

URL	Tags
https://siliconlabs.lightning.force.com/sfc/servl…	vendor-advisorypermissions-required
https://github.com/SiliconLabs/matter/tree/releas…	patch

Impacted products

1 product

Vendor	Product	Version
Silicon Labs	Silicon Labs Matter Github	Affected: 0 (semver)

Credits

Junming C. (@Chapoly1305) and Prof. Qiang Zeng of George Mason University

Show details on NVD website

JSON

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GHSA-WM5H-R2QH-R97H

Vulnerability from github – Published: 2026-07-23 21:31 – Updated: 2026-07-23 21:31

Details

Severity

8.7 (High)


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

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-6924"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-336"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-23T21:17:05Z",
    "severity": "HIGH"
  },
  "details": "A bug in the entropy initialization for SiWx917 causes the DRBG to use a predictable seed. As such, all random numbers generated in the Matter code use the same stream of numbers. This vulnerability was discovered after the impacted repository was already deprecated.",
  "id": "GHSA-wm5h-r2qh-r97h",
  "modified": "2026-07-23T21:31:03Z",
  "published": "2026-07-23T21:31:03Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-6924"
    },
    {
      "type": "WEB",
      "url": "https://github.com/SiliconLabs/matter/tree/release_2.3.1-1.3"
    },
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  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.

Action not permitted

CVE-2026-6924 (GCVE-0-2026-6924)

GHSA-WM5H-R2QH-R97H

Tags

Sightings

Nomenclature