CVE-2025-3873 Buffer overflow in Si91x crypto APIs
A buffer overflow in Silicon Labs SiWx91x crypto APIs allows attackers to corrupt host application data or execute code via unchecked output buffer sizes.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2025-3873?
CVE-2025-3873 is a medium-severity memory corruption vulnerability in silabs.com WiseConnect, published on 25 Jul 2025. Any signed-in user can exploit it over the network, with no action from the victim.
Official 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
Weakness: CWE-787
Which versions are affected by CVE-2025-3873?
How do I fix CVE-2025-3873?
No fix has been published for CVE-2025-3873 yet. Limit exposure of the affected software until one is available.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2025-3873 being exploited?
There is no known exploitation of CVE-2025-3873 in the wild and no public exploit code.
Sources
Also known as GHSA-5f47-2v24-g377.