CVE-2025-4277 Tcg2Smm: improper input validation may lead to arbitrary code execution
Attackers can execute arbitrary code at System Management Mode level via improper input validation in InsydeH2O firmware.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2025-4277?
CVE-2025-4277 is a high-severity code injection vulnerability in InsydeH2O, published on 13 Aug 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
Tcg2Smm has a vulnerability which can be used to write arbitrary memory inside SMRAM and execute arbitrary code at SMM level.
Weakness: CWE-20
Which versions are affected by CVE-2025-4277?
How do I fix CVE-2025-4277?
No fix has been published for CVE-2025-4277 yet. Limit exposure of the affected software until one is available.
Upgrade, and never evaluate templates, expressions or code built from user input. More about Code injection.
Is CVE-2025-4277 being exploited?
There is no known exploitation of CVE-2025-4277 in the wild and no public exploit code.
Sources
Also known as GHSA-xcpg-24q4-26m3.