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TI-2021-14828 Aliases CVE-2021-36647GHSA-7wwm-8prx-hpg2

Use of a Broken or Risky Cryptographic Algorithm in the function mbedtls_mpi_exp_mod() in…

Priority LOW 21CWE-327Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
High
Impact type
Information disclosure
Confidentiality · integrity · availability
High · None · None
Fix status
No fix listed

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA. Impact type from CWE-327.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00172 6th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
——all versions—No fix listedCNA
  • — Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:a:arm:mbed_tls:*:*:*:*:*:*:*:*before 2.16.11; 2.17.0 to before 2.27.0VulnerableArm
cpe:2.3:a:trustedfirmware:mbed_tls:*:*:*:*:*:*:*:*2.28.0 to before 3.0.0VulnerableOP-TEE
  • cpe:2.3:a:arm:mbed_tls:*:*:*:*:*:*:*:* Versions before 2.16.11; 2.17.0 to before 2.27.0 Vulnerable ·Arm
  • cpe:2.3:a:trustedfirmware:mbed_tls:*:*:*:*:*:*:*:* Versions 2.28.0 to before 3.0.0 Vulnerable ·OP-TEE

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-36647
  2. 2026-10-03 Alias added: GHSA-7wwm-8prx-hpg2

References

Advisory 3

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences