CVE-2021-36647

Description

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.

Category

4.7
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.04%
Vendor Advisory mbed.org
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://kouzili.com/Load-Step.pdf third party advisory
https://github.com/ARMmbed/mbedtls/releases/ third party advisory
https://tls.mbed.org/tech-updates/security-advisories/mbedtls-security-advisory-2021-07-1 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-36647?
CVE-2021-36647 has been scored as a medium severity vulnerability.
How to fix CVE-2021-36647?
To fix CVE-2021-36647, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-36647 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-36647 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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