Openenclave
CVE-2023-37479
HIGH
Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Lifecycle Timeline
1DescriptionNVD
Open Enclave is a hardware-agnostic open source library for developing applications that utilize Hardware-based Trusted Execution Environments, also known as Enclaves. There are two issues that are mitigated in version 0.19.3. First, Open Enclave SDK does not properly sanitize the MXCSR register on enclave entry. This makes applications vulnerable to MXCSR Configuration Dependent Timing (MCDT) attacks, where incorrect MXCSR values can impact instruction retirement by at most one cycle, depending on the (secret) data operand value. Please find more details in the guidance from Intel in the references. Second, Open Enclave SDK does not sanitize x86's alignment check flag RFLAGS.AC on enclave entry. This opens up the possibility for a side-channel attacker to be notified for every unaligned memory access performed by the enclave. The issue has been addressed in version 0.19.3 and the current master branch. Users will need to recompile their applications against the patched libraries to be protected from this vulnerability. There are no known workarounds for this vulnerability.
AnalysisAI
Open Enclave is a hardware-agnostic open source library for developing applications that utilize Hardware-based Trusted Execution Environments, also known as Enclaves. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
Technical ContextAI
This vulnerability is classified under CWE-665. Open Enclave is a hardware-agnostic open source library for developing applications that utilize Hardware-based Trusted Execution Environments, also known as Enclaves. There are two issues that are mitigated in version 0.19.3. First, Open Enclave SDK does not properly sanitize the MXCSR register on enclave entry. This makes applications vulnerable to MXCSR Configuration Dependent Timing (MCDT) attacks, where incorrect MXCSR values can impact instruction retirement by at most one cycle, depending on the (secret) data operand value. Please find more details in the guidance from Intel in the references. Second, Open Enclave SDK does not sanitize x86's alignment check flag RFLAGS.AC on enclave entry. This opens up the possibility for a side-channel attacker to be notified for every unaligned memory access performed by the enclave. The issue has been addressed in version 0.19.3 and the current master branch. Users will need to recompile their applications against the patched libraries to be protected from this vulnerability. There are no known workarounds for this vulnerability. Affected products include: Openenclave. Version information: version 0.19.3..
RemediationAI
A vendor patch is available. Apply the latest security update as soon as possible. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.
More in Openenclave
View allIn Open Enclave before version 0.12.0, an information disclosure vulnerability exists when an enclave application using
In openenclave before 0.10.0, enclaves that use x87 FPU operations are vulnerable to tampering by a malicious host appli
Same weakness CWE-665 – Improper Initialization
View allSame technique Information Disclosure
View allShare
External POC / Exploit Code
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