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.

Problem type

Stack-based Buffer Overflow

Affected products

OpenSC

OpenSC

< 0.27.0 - AFFECTED

< 0358817ec74aeca654f83e7709c7720b14c5db59 - AFFECTED

References

github.com

https://github.com/OpenSC/OpenSC/commit/0358817ec74aeca654f83e7709c7720b14c5db59

patch

vulncheck.com

https://www.vulncheck.com/advisories/opensc-buffer-overrun-in-do-key-value-via-profile-c

third-party-advisory

JSON source

https://cveawg.mitre.org/api/cve/CVE-2026-40528

Click to expand

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    "assignerShortName": "VulnCheck",
    "dateUpdated": "2026-05-29T13:58:18.086Z",
    "dateReserved": "2026-04-13T20:29:02.810Z",
    "datePublished": "2026-05-29T13:38:11.831Z",
    "state": "PUBLISHED"
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      "datePublic": "2026-03-30T00:00:00.000Z",
      "title": "OpenSC < 0.27.0 Buffer Overrun in do_key_value() via profile.c",
      "descriptions": [
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          "value": "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."
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