7.5 - CVE-2023-37479

Executive Summary

Informations
Name	CVE-2023-37479	First vendor Publication	2023-07-17
Vendor	Cve	Last vendor Modification	2024-11-21

Security-Database Scoring CVSS v3

Cvss vector : CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Overall CVSS Score	7.5
Base Score	7.5	Environmental Score	7.5
impact SubScore	3.6	Temporal Score	7.5
Exploitabality Sub Score	3.9

Attack Vector	Network	Attack Complexity	Low
Privileges Required	None	User Interaction	None
Scope	Unchanged	Confidentiality Impact	None
Integrity Impact	High	Availability Impact	None
Calculate full CVSS 3.0 Vectors scores

Security-Database Scoring CVSS v2

Cvss vector :
Cvss Base Score	N/A	Attack Range	N/A
Cvss Impact Score	N/A	Attack Complexity	N/A
Cvss Expoit Score	N/A	Authentication	N/A
Calculate full CVSS 2.0 Vectors scores

Detail

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.