CVE-2026-40528: OpenSC before 0.27.0, fixed in commit 0358817, contains a stack and heap buffer overrun vulnerability in the d

Q: How do I fix CVE-2026-40528?

opensc: upgrade to 0.27.0. Exact commands for each OS are on this page.

Q: Is CVE-2026-40528 being exploited?

CVE-2026-40528 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2026-40528 affect?

CVE-2026-40528 affects opensc. Severity is low (CVSS 3.8). 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 configur

Q: How urgent is CVE-2026-40528?

Priority 15/100. No elevated risk signals yet.

Routine

LOW 3.8UPGRADE

CVE-2026-40528 is a low-severity flaw (CVSS 3.8) affecting opensc. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

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 he

Why this priority

No elevated risk signals yet

A fixed release or distro patch exists.

Risk facts

CVSS score	3.8 (Low)
Attack vector	Physical
Attack complexity	High
Privileges needed	None
User interaction	Required
EPSS exploit chance	0.2% (top 92%)
CISA exploited list	No
Weakness	CWE-121, CWE-122
Published	2026-05-29
Last modified	2026-07-21

Publisher (CNA): VulnCheck · Vendor: opensc project

Last updated 2026-07-21 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-05-29 14:16 UTCPublished CVE record published
2026-07-21 12:10 UTCUpdated Record last modified

opensc project opensc UPGRADE

Affected: < 0.27.0

Fixed in: 0.27.0

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy opensc || rpm -q opensc || opensc --version

2. UPGRADE to 0.27.0 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade opensc

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade opensc

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2026-40528?

opensc: upgrade to 0.27.0. Exact commands for each OS are on this page.

Is CVE-2026-40528 being exploited?

CVE-2026-40528 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2026-40528 affect?

CVE-2026-40528 affects opensc. Severity is low (CVSS 3.8). 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 configur

How urgent is CVE-2026-40528?

Priority 15/100. No elevated risk signals yet.

Related CVEs

CVE-2026-40510 LOW 3.8 UPGRADE OpenSC before 0.27.0-rc1, fixed in commit 3f24f0b, contains a stack buffer overflow vulnerability in piv_proce

References

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