OpenSC provides a set of libraries and utilities to work with smart cards. Its main focus is on cards that support cryptographic operations, and facilitate their use in security applications such as authentication, mail encryption and digital signatures. OpenSC implements the standard APIs to smart cards, e.g. PKCS#11 API, Windows’ Smart Card Minidriver and macOS CryptoTokenKit.
What's new in 0.27.1
Edit 2026-04-18: Replaced the MacOS release binary due to originally uploading wrongly signed one (see #3654).
New in 0.27.1; 2026-03-31
Bugfix release to fix up infrastructure issues. There were no 0.27.0 artifacts published.
New in 0.27.0; 2026-03-30
Security
CVE-2025-13763: Several uses of potentially uninitialized memory detected by fuzzers
CVE-2025-49010: Possible write beyond buffer bounds during processing of GET RESPONSE APDU
CVE-2025-66215: Possible write beyond buffer bounds in oberthur driver
CVE-2025-66038: Possible read beyond buffer bounds when parsing historical bytes in PIV driver
CVE-2025-66037: Possible buffer overrun while parsing SPKI
More low-severity data handling issues when parsing profile configuration
General improvements - Added support for PKCS#11 3.2 in tools and pkcs11-spy and p11test(#3510) - Added support for Ed448, X448 mechanisms and improve support for Edwards and montgomery keys in general (#3090) - Support CKA_PUBKEY_KEY_INFO PKCS#11 attribute (#3090) - Various refactoring of autotools build system - Remove obsolete tokend support (#3285) - Run tests against different software PKCS#11 tokens kryoptic and NSS softokn (#3365) - Removed internal caching for current EF/DF (#3403) - Correctly detect OS-level FIPS mode in OpenSSL automatically (#3551) or through custom configuration file (#3525) - Added support for Brainpool twisted curves to pkcs11-tool and SC-HSM (#3601)
PC/SC - Handle case when smart card is removed and inserted between two subsequent calls to refresh_attributes() (#2803)
EsteID
Add support for EstEID 2025 (#3392)
Implement FinEID 4.0/4.1 support (#3505)
Add Latvian IDEMIA Cosmo X card support (#3503)
Check if PIN is locked and hint CKF_USER_PIN_TO_BE_CHANGED (#3490)
Remove obsolete FinEID cards (#3522)
Add Latvian Cosmo 8.2 card support (#3521)
D-Trust
Prevent unncecessary pin prompts on pinpad readers (#3266)
Support for D-Trust Card 5.1 & 5.4 (#3137)
Implement PIN change and unblock in dtrust-tool (#3137)
Belpic
Add supports for belpic applet version 1.8 (#3308)
OpenPGP
Implement key derived PIN format (KDF-DO) as per OpenPGP card spec v3.3 (#3398)
IDPrime
Implement 5110+ FIPS and 5110 CC (940) derive support (#3483)
Windows
Update to Wix 6 (#3435)
Fix C_WaitForSlotEvent() not working in Windows (#2919)