CVE-2021-36647: Medium severity Arm mbed TLS vulnerability

Published Jan 17, 2023
·
Updated

Use of a Broken or Risky Cryptographic Algorithm in the function mbedtlsmpiexpmod() 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.

Other sources

Use of a Broken or Risky Cryptographic Algorithm in the function mbedtlsmpiexpmod() 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.

Affected Software

13 affected componentsFixes available
Arm mbed TLS<2.16.11
Arm mbed TLS>=2.17.0<2.27.0
Arm mbed TLS>=2.28.0<3.0.0
Microsoft fluent-bit-devel-2.0.9-1.cm2.aarch64.rpm
Microsoft fluent-bit-2.0.9-1.cm2.aarch64.rpm
Microsoft cbl2 hvloader 1.0.1-5
Microsoft cbl2 hvloader 1.0.1-5
Microsoft fluent-bit-debuginfo-2.0.9-1.cm2.aarch64.rpm
Microsoft fluent-bit-debuginfo-2.0.9-1.cm2.x86_64.rpm
Microsoft fluent-bit-2.0.9-1.cm2.x86_64.rpm
Microsoft hvloader-1.0.1-6.cm2.x86_64.rpm
Microsoft fluent-bit-devel-2.0.9-1.cm2.x86_64.rpm
TrustedFirmware Mbed Tls>=2.28.0<3.0.0

Event History

Jan 17, 2023
CVE Published
via MITRE·12:00 AM
Data Sourced
via MITRE·12:00 AM
Description
Data Sourced
via NVD·09:15 PM
DescriptionSeverityWeaknessAffected Software
Jan 23, 2023
Data Sourced
via Microsoft·08:00 AM
DescriptionSeverityWeakness
Data Sourced
via Microsoft·08:00 AM
Affected Software
Updated
via Microsoft·08:00 AM
DescriptionSeverityWeakness
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Frequently Asked Questions

1

What is the vulnerability ID for this security issue?

The vulnerability ID for this security issue is CVE-2021-36647.

2

What is the severity of CVE-2021-36647?

The severity of CVE-2021-36647 is medium with a CVSS score of 4.7.

3

What software versions are affected by CVE-2021-36647?

CVE-2021-36647 affects all versions of ARM mbed TLS before 3.0.0, 2.27.0, or 2.16.11.

4

What is the CWE ID for CVE-2021-36647?

The CWE ID for CVE-2021-36647 is 327.

5

How can an attacker exploit CVE-2021-36647?

Attackers with access to precise enough timing and memory access information can exploit CVE-2021-36647.

Contact

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