CVE-2021-33626
HighCVSS 7.8Exploitation Probability (EPSS)
Low risk23th percentile - higher than 23% of all known CVEs
Summary
A vulnerability in SMM branch registers a SWSMI handler that does not sufficiently validate the allocated buffer pointer (QWORD values for CommBuffer), allowing an attacker to corrupt SMRAM memory and potentially execute arbitrary code.
Risk Assessment
An attacker could achieve arbitrary code execution in SMM, potentially leading to full system compromise.
Recommendation
Apply patches provided by the InsydeH2O vendor.
Other vulnerabilities in InsydeH2O
See all- CVE-2022-24031High
An issue was discovered in NvmExpressDxe in InsydeH2O with kernels 5.1 through 5.5. An SMM memory corruption vulnerability allows an attacker to write fixed or predictable data to SMRAM, potentially escalating privileges to SMM.
- CVE-2022-24030High
A vulnerability in AhciBusDxe in InsydeH2O with kernel 5.1-5.5 involves SMM memory corruption, allowing an attacker to write fixed or predictable data to SMRAM, potentially leading to privilege escalation to SMM.
- CVE-2021-43615High
An issue was discovered in HddPassword in InsydeH2O with kernels 5.1 through 5.5. An SMM memory corruption vulnerability allows an attacker to write fixed or predictable data to SMRAM, potentially escalating privileges to SMM.
- CVE-2021-43323High
A vulnerability in UsbCoreDxe in InsydeH2O (kernel 5.5 to 5.0) allows an attacker to hijack execution flow of code running in System Management Mode via an SMM callout. Exploitation could lead to privilege escalation to SMM.
- CVE-2021-42554High
A vulnerability in InsydeH2O with Kernel 5.0-5.5 involves SMM memory corruption in FvbServicesRuntimeDxe, allowing an attacker to write fixed or predictable data to SMRAM, potentially leading to privilege escalation to SMM.
- CVE-2021-42113High
A vulnerability in StorageSecurityCommandDxe in InsydeH2O with Kernel 5.1-5.3 involves an SMM callout that allows an attacker to hijack execution flow of code running in System Management Mode, potentially leading to privilege escalation to SMM.
- CVE-2021-42060High
A vulnerability in InsydeH2O Kernel allows an attacker to hijack execution flow of code running in System Management Mode via an Int15ServiceSmm SMM callout. Exploiting this issue could lead to escalating privileges to SMM.
- CVE-2021-42059Medium
In InsydeH2O Kernel 5.0 through 5.4 before specific versions, a stack-based buffer overflow in the UEFI DisplayTypeDxe DXE driver can lead to arbitrary code execution.
- CVE-2021-41841High
A vulnerability in AhciBusDxe in InsydeH2O with kernel 5.0-5.5 allows an attacker to access System Management Mode and execute arbitrary code, due to inclusion of functionality from an untrusted control sphere.
- CVE-2021-41840High
A vulnerability in NvmExpressDxe in InsydeH2O with kernel 5.0-5.5 allows an attacker to access System Management Mode and execute arbitrary code, due to inclusion of functionality from an untrusted control sphere.
Original NVD description (English source)
A vulnerability exists in SMM (System Management Mode) branch that registers a SWSMI handler that does not sufficiently check or validate the allocated buffer pointer(QWORD values for CommBuffer). This can be used by an attacker to corrupt data in SMRAM memory and even lead to arbitrary code execution.