Name: CVE-2026-40528: Stack-based Buffer Overflow
Creator: Rapid7
Published: 2026-05-29T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2026-40528, CWE-121, CWE-122, CVSS 7.8, EPSS 0.00154

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.

CVSS Details

CVSS 4.0 Base Score: 1 (LOW)
CVSS 4.0 Vector: (CVSS:4.0/AV:P/AC:H/AT:N/PR:N/UI:P/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X)
CVSS 3.1 Base Score: 7.8
CVSS 3.1 Vector: (CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Amazon Linux Ami 2	—	Upgrade openscUpgrade opensc-debuginfo	Jul 22, 2026	Jul 22, 2026
Amazon_linux_2023	—	Upgrade opensc-debugsourceUpgrade openscUpgrade opensc-debuginfo	Jul 21, 2026	May 29, 2026
Redhat_linux	—	No solution exists	Jul 17, 2026	May 29, 2026

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CVSS Details

Covered by Rapid7

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