CVE-2025-66037: Opensc Project Opensc

Medium severity, CVSS 6.8. EPSS: 0.3% chance of exploitation in the next 30 days.

OpenSC is an open source smart card tools and middleware. Prior to version 0.27.0, feeding a crafted input to the fuzz_pkcs15_reader harness causes OpenSC to perform an out-of-bounds heap read in the X.509/SPKI handling path. Specifically, sc_pkcs15_pubkey_from_spki_fields() allocates a zero-length buffer and then reads one byte past the end of that allocation. This issue has been patched in version 0.27.0.

Affected products

• Opensc Project Opensc: before 0.27.0 (fixed in 0.27.0)

Published 2026-03-30. Last modified 2026-06-17.