OpenSC <0.27.0 PKCS#15 Init BufOv via Crafted Profile
CVE-2026-40528 Published on May 29, 2026
OpenSC < 0.27.0 Buffer Overrun in do_key_value() via profile.c
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.
Vulnerability Analysis
CVE-2026-40528 is exploitable with physical access, requires user interaction. This vulnerability is consided to have a high level of attack complexity. The potential impact of an exploit of this vulnerability is considered to be low. considered to have a small impact on confidentiality and integrity and availability.
Weakness Types
What is a Stack Overflow Vulnerability?
A stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function).
CVE-2026-40528 has been classified to as a Stack Overflow vulnerability or weakness.
Heap-based Buffer Overflow
A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().
Affected Versions
OpenSC:- Before 0.27.0 is affected.
- Before 0358817ec74aeca654f83e7709c7720b14c5db59 is affected.