src/tools/pkcs11-tool.c in pkcs11-tool in OpenSC 0.11.7, when used with unspecified third-party PKCS#11 modules, generates RSA keys with incorrect public exponents, which allows attackers to read the cleartext form of messages that were intended to be encrypted.

Multiple stack-based buffer overflows in libopensc in OpenSC 0.11.13 and earlier allow physically proximate attackers to execute arbitrary code via a long serial-number field on a smart card, related to (1) card-acos5.c, (2) card-atrust-acos.c, and (3) card-starcos.c.

OpenSC before 0.11.7 allows physically proximate attackers to bypass intended PIN requirements and read private data objects via a (1) low level APDU command or (2) debugging tool, as demonstrated by reading the 4601 or 4701 file with the opensc-explorer or opensc-tool program.