Process memory corruption via mismatched APDU buffer length
Published Mar 30, 2026 · Updated Mar 30, 2026
Stack-based buffer overflow in OpenSC before 0.27.0 allows physically proximate attackers to corrupt process memory via a crafted token. The Oberthur driver's auth_compute_signature function supplies an APDU response length larger than its stack buffer, so oversized card data is written past the buffer bounds. Exploitation requires a crafted USB device or smart card to be present while a user or administrator uses the token, and can crash or corrupt an OpenSC-based application.
Summary
What happened
Stack-based buffer overflow in OpenSC before 0.27.0 allows physically proximate attackers to corrupt process memory via a crafted token. The Oberthur driver's auth_compute_signature function supplies an APDU response length larger than its stack buffer, so oversized card data is written past the buffer bounds. Exploitation requires a crafted USB device or smart card to be present while a user or administrator uses the token, and can crash or corrupt an OpenSC-based application.
The record
- CVE
- CVE-2025-66215
- Published
- Mar 30, 2026
- Updated
- Mar 30, 2026
- Vendor
- OpenSC Project
- Product
- OpenSC
- Classifications
- CWE-121, T1200
- Attack vector
- physical
- Privileges
- unauthenticated
Timeline
How it unfolded
- Mar 30, 2026CVE publishedPublication date reported by the CVE source.
- Mar 30, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=< 0.27.0
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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