Out-of-bounds Read in Opensc
CVE-2025-66037
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.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 3.9 (Low). Vector: CVSS:3.1/AV:P/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L.
EPSS exploit prediction
EPSS: 0.003 (15.1th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 15th percentile — 15.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000
Affected products
- Opensc — versions < 0.27.0
- Opensc Project
Weakness classification (CWE)
References
- github.com/OpenSC/OpenSC/security/advisories/GHSA-m58q-rmjm-mmfx (Exploit, Vendor Advisory)
- github.com/OpenSC/OpenSC/wiki/CVE-2025-66037 (Vendor Advisory)
Frequently asked questions
- What is CVE-2025-66037?
- CVE-2025-66037 is a low-severity vulnerability in Opensc, classified under Out-of-bounds Read. CVSS score: 3.9/10. Published 2026-03-30.
- How severe is CVE-2025-66037?
- Low severity. CVSS v3 base score is 3.9 out of 10.