CVE-2025-3873Network attack vector

Host memory corruption via unchecked crypto output buffers

Published Jul 25, 2025 · Updated Jul 25, 2025

Out-of-bounds writes in Silicon Labs WiSeConnect SDK before 3.4.0 allow remote authenticated users to corrupt Cortex-M4 host memory. The sl_si91x_aes, sl_si91x_gcm, sl_si91x_ccm, and sl_si91x_sha APIs write results into caller-supplied output buffers without first verifying their capacity. Exploitation requires low-privilege network access and a host application that passes attacker-influenced work to an affected API; the documented consequence is host data corruption.

CVSS severity6.0
Medium
EPSS probability0.31%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Out-of-bounds writes in Silicon Labs WiSeConnect SDK before 3.4.0 allow remote authenticated users to corrupt Cortex-M4 host memory. The sl_si91x_aes, sl_si91x_gcm, sl_si91x_ccm, and sl_si91x_sha APIs write results into caller-supplied output buffers without first verifying their capacity. Exploitation requires low-privilege network access and a host application that passes attacker-influenced work to an affected API; the documented consequence is host data corruption.

The record

CVE
CVE-2025-3873
Published
Jul 25, 2025
Updated
Jul 25, 2025
Vendor
Sigma Designs
Product
WiSeConnect SDK
Classifications
CWE-787, CAPEC-100
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jul 25, 2025CVE publishedPublication date reported by the CVE source.
  2. Jul 25, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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

  1. Affected versionversion=3.0.0 <3.4.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Sigma Designs · WiSeConnect SDKversion=3.0.0 <3.4.0

Published CVSS scores

6.0Silicon LabsCVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:L/VI:H/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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-787Out-of-bounds Write
CAPEC-100Overflow Buffers

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

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Your stack

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