Vulnerability · Published May 29, 2026 · Assigned by VulnCheck

CVE-2026-40528OpenSC < 0.27.0 Buffer Overrun in do_key_value() via profile.c

Low 3.8

In plain English

A low-severity stack buffer overflow in OpenSC from OpenSC. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 8% of all known vulnerabilities).

Severity (CVSS 3.1)3.8Low

Exploit odds (30 days)0.2%top 91.6% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

OpenSC before 0.27.0, fixed in commit 0358817, contains a stack and heap buffer overrun vulnerability in the do_key_value() function in src/pkcs15init/profile.c that allows attackers to corrupt memory by supplying a crafted profile configuration file. During pkcs15-init invocation, a key value entry beginning with '=' followed by more than sizeof(keybuf) characters is copied into keybuf via memcpy without a length check, causing both stack and heap buffer overruns.

Affected products (as reported)

Vendor	Product	Versions
OpenSC	OpenSC	0 – before 0.27.00 – before 0358817ec74aeca654f83e7709c7720b14c5db59

Weakness: CWE-121, CWE-122 · Vector: CVSS:3.1/AV:P/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:L

In plain English

Official description

Affected products (as reported)

References