CVE-2026-40528: OpenSC < 0.27.0 Buffer Overrun in do_key_value() via profile.c
Noroxi assessment
Priority: Monitor (action score 4/100)
- The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
- Probability of exploitation in the next 30 days: 0.18% (FIRST EPSS).
- Physical access to the device is required. No account or password is required. Special conditions such as timing or configuration are required.
- Fixed version: OpenSC OpenSC 0.27.0, 0358817ec74aeca654f83e7709c7720b14c5db59.
Low priority for now. Upgrade to OpenSC OpenSC 0.27.0, 0358817ec74aeca654f83e7709c7720b14c5db59 or later.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
Primary sources: NVD · CVE.org · FIRST EPSS
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.
- Published
- May 29, 2026
- Updated
- Jul 21, 2026
- EPSS
- 0.1% · 8th percentile
- CWE
- CWE-121
Report tools
Action score
4
Monitor
Low priority for now.
- CVSS
- 4 / 40 · 1.0 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.1%
CISA SSVC decision
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- —
- CNA · VulnCheck
- 1.0
- NVD has not scored this yet; the score shown is the CNA’s.
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
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- A fix has been released
If any of these changes, we'll tell you in the daily email digest.
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Noroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
| Vendor | Product | CPE |
|---|---|---|
| opensc project | opensc | cpe:2.3:a:opensc_project:opensc |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- opensc project openscbefore 0.27.0
Versions reported by the vendor
Affected version ranges reported by the assigning authority (VulnCheck). Independent of NVD's CPE analysis and usually ahead of it.
OpenSC OpenSC
- before 0.27.0affected · semver
- before 0358817ec74aeca654f83e7709c7720b14c5db59affected · git
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| openSUSE:Leap 16.0 | opensc | before 0.26.1-160000.5.1 | 0.26.1-160000.5.1 |
| openSUSE:Tumbleweed | opensc | before 0.27.1-2.1 | 0.27.1-2.1 |
| SUSE:Linux Enterprise Micro 5.3 | opensc | before 0.22.0-150400.3.17.1 | 0.22.0-150400.3.17.1 |
| SUSE:Linux Enterprise Module for Basesystem 15 SP7 | opensc | before 0.22.0-150600.11.11.1 | 0.22.0-150600.11.11.1 |
| SUSE:Linux Micro 6.0 | opensc | before 0.24.0-6.1 | 0.24.0-6.1 |
| SUSE:Linux Micro 6.1 | opensc | before 0.24.0-slfo.1.1_4.1 | 0.24.0-slfo.1.1_4.1 |
Same product
opensc project: all recordsOther highest-scoring records for the same primary product.
- CVE-2019-6502sc_context_create in ctx.c in libopensc in OpenSC 0.19.0 has a memory leak, as demonstrated by a call from eidenv.31Monitor
- CVE-2021-34193Stack overflow vulnerability in OpenSC smart card middleware before 0.23 via crafted responses to APDUs.30Monitor
- CVE-2019-16058An issue was discovered in the pam_p11 component 0.2.0 and 0.3.0 for OpenSC.30Monitor
Published before and after this one in the same product
- ← EarlierCVE-2025-66038Mar 30, 2026 · OpenSC: `sc_compacttlv_find_tag` can return out-of-bounds pointers27Monitor
- ← EarlierCVE-2025-66215Mar 30, 2026 · OpenSC: Stack-buffer-overflow WRITE in card-oberthur27Monitor
- ← EarlierCVE-2026-40510May 29, 2026 · OpenSC < 0.27.0-rc1 Stack Buffer Overflow via piv_process_history() in card-piv.c4Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| OpenSC OpenSC | 0.27.0 | Vendor (CNA) |
| OpenSC OpenSC | 0358817ec74aeca654f83e7709c7720b14c5db59 | Vendor (CNA) |
| opensuse:opensc | 0.27.1-2.1 · openSUSE:Tumbleweed | Package registry (OSV) |
| suse:opensc | 0.24.0-6.1 · SUSE:Linux Micro 6.0 | Package registry (OSV) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
- Nicholas CarliniAnthropicfinder
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
- CVE-2025-4901060 days apartOpenSC: Stack-buffer-overflow WRITE in GET RESPONSE27Monitor
- CVE-2025-6621560 days apartOpenSC: Stack-buffer-overflow WRITE in card-oberthur27Monitor
- CVE-2026-405100 days apartOpenSC < 0.27.0-rc1 Stack Buffer Overflow via piv_process_history() in card-piv.c4Monitor
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Physical access to the device is required.
- No account or password is required.
- Special conditions such as timing or configuration are required.
If successful
- Confidentiality
- Integrity
- Availability
- Attack vector
- Physical
- Attack complexity
- High
- Privileges required
- None
- User interaction
- P
- Scope
- X
Weakness class (CWE)
CWE-121 · Stack-based Buffer OverflowCVSS 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
nvd-secondary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
MITRE has no CAPEC/ATT&CK mapping for this CWE.
Change log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (1 more)Show less
Vendor advisories and official records. Exploit/PoC links are deliberately left out.