Vulnerability · Published Aug 13, 2025 · Assigned by Insyde

CVE-2025-4277Tcg2Smm: improper input validation may lead to arbitrary code execution

High 7.5

In plain English

A high-severity improper input validation in InsydeH2O from Insyde Software. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 4% of all known vulnerabilities).

Severity (CVSS 3.1)7.5High
Exploit odds (30 days)0.2%top 95.6% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

Tcg2Smm has a vulnerability which can be used to write arbitrary memory inside SMRAM and execute arbitrary code at SMM level.

Affected products (as reported)

VendorProductVersions
Insyde Software InsydeH2O Kernel 5.2 – before 05.2A.21Kernel 5.3 – before 05.39.21Kernel 5.4 – before 05.47.21Kernel 5.5 – before 05.55.21Kernel 5.6 – before 05.62.21Kernel 5.7 – before 05.71.21

Weakness: CWE-20 · Vector: CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H

References