CVE-2021-36647

Use of a Broken or Risky Cryptographic Algorithm in the function mbedtls_mpi_exp_mod() in lignum.c in Mbed TLS Mbed TLS all versions before 3.0.0, 2.27.0 or 2.16.11 allows attackers with access to precise enough timing and memory access information (typically an untrusted operating system attacking a secure enclave such as SGX or the TrustZone secure world) to recover the private keys used in RSA.

CVSS v3 4.7 MEDIUM

4.7^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.0 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/ARMmbed/mbedtls/releases/	Third Party Advisory
https://kouzili.com/Load-Step.pdf	Third Party Advisory
https://tls.mbed.org/tech-updates/security-advisories/mbedtls-security-advisory-2021-07-1	Vendor Advisory
https://github.com/ARMmbed/mbedtls/releases/	Third Party Advisory
https://kouzili.com/Load-Step.pdf	Third Party Advisory
https://tls.mbed.org/tech-updates/security-advisories/mbedtls-security-advisory-2021-07-1	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:arm:mbed_tls::::::::
	cpe:2.3:a:arm:mbed_tls::::::::
	cpe:2.3:a:arm:mbed_tls::::::::

History

No history.

Information

Published : 2023-01-17 21:15

Updated : 2025-04-08 21:15

NVD link : CVE-2021-36647

Mitre link : CVE-2021-36647

CVE.ORG link : CVE-2021-36647

JSON object : View

Products Affected

arm

mbed_tls

CWE

CWE-327

Use of a Broken or Risky Cryptographic Algorithm

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