CVE-2026-103531 OpenSC card-setcos.c setcos_construct_fci_44 stack-based overflow
A stack-based buffer overflow in OpenSC allows remote attackers to execute arbitrary code or cause denial of service via manipulated arguments.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-103531?
CVE-2026-103531 is a medium-severity memory corruption vulnerability in OpenSC, published on 1 Oct 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Official description
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.
Which versions are affected by CVE-2026-103531?
How do I fix CVE-2026-103531?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-103531 being exploited?
There is no known exploitation of CVE-2026-103531 in the wild and no public exploit code.
Sources
Also known as AZL-105342, CLSA-2026-1791470029, DEBIAN-CVE-2026-103531, GHSA-m2qg-x6vj-xmrg, UBUNTU-CVE-2026-103531.