CVE-2025-9231

Timing side-channel in SM2 algorithm on 64 bit ARM

Published Sep 30, 2025 CVSS 3.1 · 5.9 Medium EPSS 1.6% KEV · Not listed
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

Sign in to view the affected projects.

Advisories

Source ID Title
Debian DSA Debian DSA DSA-6015-1 openssl security update
EUVD EUVD EUVD-2025-31728 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.
Ubuntu USN Ubuntu USN USN-7786-1 OpenSSL vulnerabilities
History
Type Values Removed Values Added
First Time appeared Siemens
Siemens ruggedcom Rst2428p
Siemens ruggedcom Rst2428p Firmware
Siemens scalance Xc316-8
Siemens scalance Xc319-4
Siemens scalance Xc324-4
Siemens scalance Xc324-4eec
Siemens scalance Xc332
Siemens scalance Xc416-8
Siemens scalance Xc419-4
Siemens scalance Xc424-4
Siemens scalance Xc432
Siemens scalance Xch328
Siemens scalance Xcm324
Siemens scalance Xcm328
Siemens scalance Xcm332
Siemens scalance Xr302-32
Siemens scalance Xr322-12
Siemens scalance Xr326-8
Siemens scalance Xr326-8eec
Siemens scalance Xr502-32
Siemens scalance Xr522-12
Siemens scalance Xr524-8c
Siemens scalance Xr524-8wg
Siemens scalance Xr526-8
Siemens scalance Xr526-8c
Siemens scalance Xr528-6m
Siemens scalance Xr552-12m
Siemens scalance Xrh334
Siemens scalance Xrm334
Siemens sidis Secured Smartplug
Siemens sidis Secured Smartplug Firmware
Siemens simatic Cn 4100
Siemens simatic Cn 4100 Firmware
Siemens sinec Os
CPEs cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*
cpe:2.3:h:siemens:ruggedcom_rst2428p:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:scalance_xc316-8:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:scalance_xc319-4:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:scalance_xc324-4:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:scalance_xc324-4eec:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:scalance_xc332:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:scalance_xc416-8:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:scalance_xc419-4:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:scalance_xc424-4:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:scalance_xc432:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:scalance_xch328:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:scalance_xcm324:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:scalance_xcm328:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:scalance_xcm332:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:scalance_xr302-32:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:scalance_xr322-12:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:scalance_xr326-8:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:scalance_xr326-8eec:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:scalance_xr502-32:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:scalance_xr522-12:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:scalance_xr524-8c:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:scalance_xr524-8wg:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:scalance_xr526-8:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:scalance_xr526-8c:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:scalance_xr528-6m:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:scalance_xr552-12m:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:scalance_xrh334:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:scalance_xrm334:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:sidis_secured_smartplug:-:*:*:*:*:*:*:*
cpe:2.3:h:siemens:simatic_cn_4100:-:*:*:*:*:*:*:*
cpe:2.3:o:siemens:ruggedcom_rst2428p_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:sidis_secured_smartplug_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_cn_4100_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:sinec_os:*:*:*:*:*:*:*:*
Vendors & Products Siemens
Siemens ruggedcom Rst2428p
Siemens ruggedcom Rst2428p Firmware
Siemens scalance Xc316-8
Siemens scalance Xc319-4
Siemens scalance Xc324-4
Siemens scalance Xc324-4eec
Siemens scalance Xc332
Siemens scalance Xc416-8
Siemens scalance Xc419-4
Siemens scalance Xc424-4
Siemens scalance Xc432
Siemens scalance Xch328
Siemens scalance Xcm324
Siemens scalance Xcm328
Siemens scalance Xcm332
Siemens scalance Xr302-32
Siemens scalance Xr322-12
Siemens scalance Xr326-8
Siemens scalance Xr326-8eec
Siemens scalance Xr502-32
Siemens scalance Xr522-12
Siemens scalance Xr524-8c
Siemens scalance Xr524-8wg
Siemens scalance Xr526-8
Siemens scalance Xr526-8c
Siemens scalance Xr528-6m
Siemens scalance Xr552-12m
Siemens scalance Xrh334
Siemens scalance Xrm334
Siemens sidis Secured Smartplug
Siemens sidis Secured Smartplug Firmware
Siemens simatic Cn 4100
Siemens simatic Cn 4100 Firmware
Siemens sinec Os
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'}

cvssV3_1

{'score': 5.9, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N'}

Type Values Removed Values Added
First Time appeared Openssl
Openssl openssl
Vendors & Products Openssl
Openssl openssl
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'}

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
Weaknesses

Sources

Status
PUBLISHED
Assigner
openssl
Published
Updated
Nov 6, 2026, 9:45 PM
Reserved
Aug 20, 2025, 8:38 AM
Status
Analyzed
Published
Sep 30, 2025, 2:15 PM
Modified
Nov 9, 2026, 8:51 PM
Severity
Moderate
Public date
Sep 30, 2025, 11:59 PM