Buffer overflow in Opensc
CVE-2026-103531
A flaw has been found in OpenSC up to 0.27.1. The impacted element is the function setcos_construct_fci_44 of the file src/libopensc/card-setcos.c. Executing a manipulation of the argument type_attr can lead to stack-based buffer overflow. The attack can be launched remotely. This patch is called ad730304052937c32b4eb489a06835ac6123632c. It is best practice to apply a patch to resolve this issue.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:L.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
- Opensc — versions 0.27.0, 0.27.1
Weakness classification (CWE)
References
- github.com/OpenSC/OpenSC/ (product)
- github.com/OpenSC/OpenSC/commit/ad730304052937c32b4eb489a06835ac6123632c (patch)
- github.com/OpenSC/OpenSC/pull/3812 (issue-tracking, patch)
- vuldb.com/cve/CVE-2026-103531 (third-party-advisory)
- vuldb.com/submit/956910 (third-party-advisory)
- vuldb.com/vuln/412343 (technical-description, vdb-entry)
- vuldb.com/vuln/412343/cti (signature, permissions-required)
Frequently asked questions
- What is CVE-2026-103531?
- CVE-2026-103531 is a medium-severity vulnerability in Opensc, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 5.5/10. Published 2026-10-01.
- How severe is CVE-2026-103531?
- Medium severity. CVSS v3 base score is 5.5 out of 10.