CVE-2021-43393

Severity: medium (CVSS 6.2 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2022-03-04 · updated 2026-06-17
Weakness: CWE-347

Description

STMicroelectronics STSAFE-J 1.1.4, J-SAFE3 1.2.5, and J-SIGN sometimes allow attackers to abuse signature verification. This is associated with the ECDSA signature algorithm on the Java Card J-SAFE3 and STSAFE-J platforms exposing a 3.0.4 Java Card API. It is exploitable for STSAFE-J in closed configuration and J-SIGN (when signature verification is activated) but not for J-SAFE3 EPASS BAC and EAC products. It might also impact other products based on the J-SAFE-3 Java Card platform.

Affected products

St J-Safe3 Firmware: 1.2.5
Stsafe-J Firmware: 1.1.4

References

https://community.st.com/s/toparticles
https://www.cert.ssi.gouv.fr/avis/CERTFR-2022-AVI-169/
https://community.st.com/s/toparticles
https://www.cert.ssi.gouv.fr/avis/CERTFR-2022-AVI-169/

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