CVE-2025-3873: silabs.com WiseConnect · Out-of-bounds Write
Affects silabs.com WiseConnectSource CVE Database V5
Not known to be exploited · CVSS 6.0 Medium.
Data as of 26 Oct 2026, 06:26 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 25% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 25 Jul 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-26.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| silabs.com WiseConnect | Affected
| Fixed in– |
AI-suggested
European organizations should take proactive steps to mitigate this vulnerability: 1) Identify all devices and systems using Silicon Labs SiWx91x microcontrollers with WiseConnect versions prior to 3.4.0. 2) Coordinate with Silicon Labs for timely updates or patches; monitor official channels for patch releases. 3) Until patches are available, implement network segmentation and strict access controls to limit exposure of vulnerable devices to untrusted networks. 4) Employ runtime integrity monitoring on host Cortex-M4 applications to detect anomalous behavior or data corruption early. 5) Conduct thorough testing of cryptographic functions in affected devices to identify potential failures. 6) Where feasible, replace or upgrade devices to versions with fixed firmware. 7) Incorporate vulnerability scanning and asset management tools to maintain visibility of affected devices. 8) Educate operational technology (OT) and IoT security teams about the risks and signs of exploitation related to this vulnerability. These targeted measures go beyond generic advice by focusing on device identification, network isolation, and proactive monitoring specific to the SiWx91x platform and its cryptographic APIs.
Description
The following APIs for the Silcon Labs SiWx91x prior to vesion 3.4.0 failed to check the size of the output buffer of the caller which could lead to data corruption on the host (Cortex-M4) application.sl_si91x_aes sl_si91x_gcm sl_si91x_ccm sl_si91x_sha