Issue summary: A timing side-channel which could potentially allow remote
recovery of the private key exists in the SM2 algorithm implementation on 64 bit
ARM platforms.

Impact summary: A timing side-channel in SM2 signature computations on 64 bit
ARM platforms could allow recovering the private key by an attacker..

While remote key recovery over a network was not attempted by the reporter,
timing measurements revealed a timing signal which may allow such an attack.

OpenSSL does not directly support certificates with SM2 keys in TLS, and so
this CVE is not relevant in most TLS contexts. However, given that it is
possible to add support for such certificates via a custom provider, coupled
with the fact that in such a custom provider context the private key may be
recoverable via remote timing measurements, we consider this to be a Moderate
severity issue.

The FIPS modules in 3.5, 3.4, 3.3, 3.2, 3.1 and 3.0 are not affected by this
issue, as SM2 is not an approved algorithm.
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Tue, 30 Sep 2025 20:15:00 +0000

Type Values Removed Values Added
Metrics cvssV3_1

{'score': 6.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L'}

ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Tue, 30 Sep 2025 13:30:00 +0000

Type Values Removed Values Added
Description Issue summary: A timing side-channel which could potentially allow remote recovery of the private key exists in the SM2 algorithm implementation on 64 bit ARM platforms. Impact summary: A timing side-channel in SM2 signature computations on 64 bit ARM platforms could allow recovering the private key by an attacker.. While remote key recovery over a network was not attempted by the reporter, timing measurements revealed a timing signal which may allow such an attack. OpenSSL does not directly support certificates with SM2 keys in TLS, and so this CVE is not relevant in most TLS contexts. However, given that it is possible to add support for such certificates via a custom provider, coupled with the fact that in such a custom provider context the private key may be recoverable via remote timing measurements, we consider this to be a Moderate severity issue. The FIPS modules in 3.5, 3.4, 3.3, 3.2, 3.1 and 3.0 are not affected by this issue, as SM2 is not an approved algorithm.
Title Timing side-channel in SM2 algorithm on 64 bit ARM
Weaknesses CWE-385
References

cve-icon MITRE

Status: PUBLISHED

Assigner: openssl

Published:

Updated: 2025-09-30T19:28:28.380Z

Reserved: 2025-08-20T08:38:09.832Z

Link: CVE-2025-9231

cve-icon Vulnrichment

Updated: 2025-09-30T19:28:07.505Z

cve-icon NVD

Status : Received

Published: 2025-09-30T14:15:41.190

Modified: 2025-09-30T20:15:41.220

Link: CVE-2025-9231

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.