medium4.7
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.…
Impact
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.
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Arm | Mbed Tls | before 2.16.11 from 2.17.0 before 2.27.0 |
| Trustedfirmware | Mbed Tls | from 2.28.0 before 3.0.0 |
Weakness classification
References
- NVD record
- CVE.org record
- https://github.com/ARMmbed/mbedtls/releases/
- https://kouzili.com/Load-Step.pdf
- https://tls.mbed.org/tech-updates/security-advisories/mbedtls-security-advisory-2021-07-1
- https://github.com/ARMmbed/mbedtls/releases/
- https://kouzili.com/Load-Step.pdf
- https://lists.debian.org/debian-lts-announce/2025/06/msg00034.html
- https://tls.mbed.org/tech-updates/security-advisories/mbedtls-security-advisory-2021-07-1