Vulnerability Monitor

The vendors, products, and vulnerabilities you care about

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.


Security Impact Summary

This vulnerability carries a MEDIUM severity rating with a CVSS v3.1 score of 4.7, requiring local system access to exploit but requires specific conditions to be met without requiring user interaction requiring only low-level privileges . The vulnerability impacts confidentiality (data exposure), for affected systems. Impacting 1 product from arm organizations running these solutions should prioritize assessment and patching.

Historical Context

Reported in 2023, this vulnerability emerged during an era marked by increased sophistication in supply chain attacks, cloud infrastructure vulnerabilities, and software-as-a-service (SaaS) security challenges. Security practices during this period emphasized zero-trust architectures, container security, and API protection.


Published

2023-01-17T21:15:10.880

Last Modified

2025-11-03T20:15:49.343

Status

Modified

Source

[email protected]

Severity

CVSSv3.1: 4.7 (MEDIUM)

Weaknesses
  • Type: Primary
    CWE-327
  • Type: Secondary
    CWE-327

Affected Vendors & Products
Type Vendor Product Version/Range Vulnerable?
Application arm mbed_tls < 2.16.11 Yes
Application arm mbed_tls < 2.27.0 Yes
Application arm mbed_tls < 3.0.0 Yes

References

How SecUtils Interprets This CVE

SecUtils normalizes and enriches National Vulnerability Database (NVD) records by standardizing vendor and product identifiers, aggregating vulnerability metadata from both NVD and MITRE sources, and providing structured context for security teams. For arm's affected products, we extract Common Platform Enumeration (CPE) data, Common Weakness Enumeration (CWE) classifications, CVSS severity metrics, and reference data to enable rapid vulnerability prioritization and asset correlation. This record contains no exploit code, proof-of-concept instructions, or attack methodologies—only defensive intelligence necessary for patch management, risk assessment, and security operations.