CVE-2020-5953
HighCVSS 7.5Exploitation Probability (EPSS)
Low risk21th percentile - higher than 21% of all known CVEs
Summary
A vulnerability exists in the SWSMI handler of InsydeH2O UEFI firmware that dereferences the gRT pointer to call a GetVariable service located outside SMRAM. This can result in code execution in SMM, escalating privileges from ring 0 to ring -2.
Risk Assessment
An attacker could execute code in SMM, leading to full system compromise and firmware integrity violation.
Recommendation
Update InsydeH2O firmware to a patched version.
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 System Management Interrupt (SWSMI) handler of InsydeH2O UEFI Firmware code located in SWSMI handler that dereferences gRT (EFI_RUNTIME_SERVICES) pointer to call a GetVariable service, which is located outside of SMRAM. This can result in code execution in SMM (escalating privilege from ring 0 to ring -2).

