BlackTreeCVE Intelligence
← Back to the CVE catalogue
Full vulnerability report · 2026
CVE-2026-10275High confidence

OpenSC pkcs11-tool Key Generation pkcs11-tool.c test_kpgen_certwrite buffer overflow

Unknown · OpenSC

2.3LowCVSS 4.0
Recommended action
Patch only the product branches with a verified fix

Low technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority. Verified remediation exists for at least one product or source, but 2 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Fix availability varies by product
R
Operational reassessment

Published severity in operational context

Open reassessment dashboard →
Published severityLowOperational priority:Low, unchanged from published severity.unchanged

Evidence used

  • No CISA KEV confirmation is currently recorded.
  • EPSS is 0.30% for the current model date.

Compensating controls

  • Validate the affected product branch and deploy the verified fixed release.
  • Restrict the affected network interface to trusted sources where business-safe.
  • Monitor vendor guidance and exploitation sources for a material change.

Verification

  1. Confirm that the asset runs Unknown OpenSC and falls inside the recorded affected range.
  2. Verify the installed build against the product-specific fixed version after deployment.
  3. Validate exposure, authentication requirements and compensating controls in the actual environment.
  4. Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Mitigation target: No default targetRemediation target: Normal maintenance

This automated reassessment organises public evidence. It does not know asset exposure, business impact or control effectiveness and does not replace CVSS or a human risk decision.

Cross-source reconciliation

Remediation availability differs by product scope

Verified remediation exists for at least one product or source, but 2 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Distribution package intelligence

Release-specific package status

Debian, ubuntu findings are scoped to the named distribution, release and source package. An absent finding does not mean a package is unaffected.

5 package states
Package result overrides the generic status

BlackTree has verified remediation for at least one product or source, but the relevant distribution still reports no fixed package for 2 affected package states shown here. Treat those rows as affected with no fix until that distribution publishes a fixed version.

Repository candidate not checked

A published vendor fix does not prove that a matching update is enabled and installable on a particular asset. Confirm the local package candidate before scheduling remediation.

Distribution releaseSource packageVendor stateFixed versionEvidence
Debian trixietrixie · sourceopenscAffected, no fix publishedDebian currently tracks this release as open.Not published in this feedDebian Security Tracker ↗Source updated 6 Oct 2026
Debian bookwormbookworm · sourceopenscAffected, no fix publishedDebian currently tracks this release as open.Not published in this feedDebian Security Tracker ↗Source updated 6 Oct 2026
Debian forkyforky · sourceopenscVendor fix publishedDebian records a fixed source-package version for this release.0.27.1-2Debian Security Tracker ↗Source updated 6 Oct 2026
Debian sidsid · sourceopenscVendor fix publishedDebian records a fixed source-package version for this release.0.27.1-2Debian Security Tracker ↗Source updated 6 Oct 2026
Ubuntu 24.04 LTSnoble · esm-appsopenscUnder evaluationCanonical reports that the package might be affected and still needs evaluation or fixing.Not published in this feedCanonical Ubuntu Security ↗Source updated 6 Oct 2026
Direct vendor intelligence

Authoritative vendor CSAF and VEX advisories

Structured product status and remediation from the issuing vendor. Product-state explanations are always visible; large lists can be searched or downloaded.

1 current
CVE-2026-10275 · CSAF 2.0 · revision 12 · interimSUSE Product Security TeamCVE-2026-10275
31 known affected

The vendor explicitly identifies these products as affected by this CVE.

  • opensc as component of SUSE Linux Enterprise High Performance Computing 12 SP4
  • opensc as component of SUSE Linux Enterprise High Performance Computing 15 SP1
  • opensc as component of SUSE Linux Enterprise High Performance Computing 15 SP2
  • opensc as component of SUSE Linux Enterprise High Performance Computing 15 SP3
  • opensc as component of SUSE Linux Enterprise Server 12 SP4-LTSS
  • opensc as component of SUSE Linux Enterprise Server 12 SP4
  • opensc as component of SUSE Linux Enterprise Server 15 SP1-LTSS
  • opensc as component of SUSE Linux Enterprise Server 15 SP1
  • opensc as component of SUSE Linux Enterprise Server 15 SP2-LTSS
  • opensc as component of SUSE Linux Enterprise Server 15 SP2
  • opensc as component of SUSE Linux Enterprise Server 15 SP3-LTSS
  • opensc as component of SUSE Linux Enterprise Server 15 SP3
Summary
A flaw has been found in OpenSC up to 0.26.1. This affects the function test_kpgen_certwrite of the file src/tools/pkcs11-tool.c of the component pkcs11-tool Key Generation Module. This manipulation causes buffer overflow. The attack is possible to be carried out remotely. The complexity of an attack is rather high. It is indicated that the exploitability is difficult. The exploit has been published and may be used. Patch name: 814f745b3b6d100295f65f1935edd33d520d33ab. It is recommended to apply a patch to fix this issue.
Remediation
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
Optional official sources

National CERT insights
?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

Choose official national sources for this report. Each advisory shows its original language. Your selection is remembered on this device and included in shared links.

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current
ENISA EUVD identifier

EUVD-2026-33680

No EUVD known-exploited evidence

ENISA has published the identifier mapping but no EUVD description has been stored yet.

EUVD state
Present in the current official mapping
Known exploitation
Not present in the current ENISA EUVD known-exploited dataset. This is not proof of no exploitation.
ENISA score
Not supplied in the stored EUVD record
Advisory evidence
No linked advisory details stored yet
Recommended actionPatch only the product branches with a verified fix

Low technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority. Verified remediation exists for at least one product or source, but 2 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Fix availability varies by product
01

What, why and how

A flaw has been found in OpenSC up to 0.26.1. This affects the function test_kpgen_certwrite of the file src/tools/pkcs11-tool.c of the component pkcs11-tool Key Generation Module. This manipulation causes buffer overflow. The attack is possible to be carried out remotely. The complexity of an attack is rather high. It is indicated that the exploitability is difficult. The exploit has been published and may be used. Patch name: 814f745b3b6d100295f65f1935edd33d520d33ab. It is recommended to apply a patch to fix this issue.

What

A flaw has been found in OpenSC up to 0.26.1. This affects the function test_kpgen_certwrite of the file src/tools/pkcs11-tool.c of the component pkcs11-tool Key Generation Module. This manipulation causes buffer overflow. The attack is possible to be carried out remotely. The complexity of an attack is rather high. It is indicated that the exploitability is difficult. The exploit has been published and may be used. Patch name: 814f745b3b6d100295f65f1935edd33d520d33ab. It is recommended to apply a patch to fix this issue.

Why

The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer.

How

An attacker operating through a network path may attempt exploitation when the stated preconditions are met. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

What

A flaw has been found in OpenSC up to 0.26.1. This affects the function test_kpgen_certwrite of the file src/tools/pkcs11-tool.c of the component pkcs11-tool Key Generation Module. This manipulation causes buffer overflow. The attack is possible to be carried out remotely. The complexity of an attack is rather high. It is indicated that the exploitability is difficult. The exploit has been published and may be used. Patch name: 814f745b3b6d100295f65f1935edd33d520d33ab. It is recommended to apply a patch to fix this issue.

Why

The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer.

How

An attacker operating through a network path may attempt exploitation when the stated preconditions are met. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

02

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
No confirmed evidence

No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.

Public PoC / exploit material
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
None recorded

No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.

Likely attack path
a network path → Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Network
Privileges required
None: unauthenticated exploitation is possible
User interaction
Passive interaction required
Attack complexity
High: exploitation depends on specific conditions
Security boundary
Not a CVSS 4.0 base metric
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-120 ↗

CWE-120: Buffer Copy without Checking Size of Input ('Classic Buffer Overflow'). The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer.

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:P/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P

Common Vulnerability Scoring System 4.0: the compact vector below is decoded into plain language.

AVNetworkAttack vector: The vulnerable component can be reached over a network.ACHighAttack complexity: Successful exploitation depends on specific conditions outside the attacker's direct control.ATNoneAttack requirements: No additional deployment or execution condition is required.PRNonePrivileges required: The attacker does not need an account or existing privileges.UIPassiveUser interaction: A user must unknowingly interact with the vulnerable system.VCLowVulnerable-system confidentiality: A successful attack can cause a limited loss.VILowVulnerable-system integrity: A successful attack can cause a limited loss.VALowVulnerable-system availability: A successful attack can cause a limited loss.SCNoneSubsequent-system confidentiality: No direct loss is represented by this metric.SINoneSubsequent-system integrity: No direct loss is represented by this metric.SANoneSubsequent-system availability: No direct loss is represented by this metric.
Post-exploitation / living off the land
No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
NetworkUnauthenticatedCWE-120
A

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

BSI · German · WID-SEC-2026-1769OpenSC: Schwachstelle ermöglicht Codeausführung

Ein entfernter, anonymer Angreifer kann eine Schwachstelle in OpenSC ausnutzen, um beliebigen Programmcode auszuführen.

Official advisory ↗
Cyber Security Agency of Singapore · English · CSA-SB-20260603Security Bulletin 3 Jun 2026

The Cyber Security Agency of Singapore included this CVE in its official Security Bulletin 3 Jun 2026, published on 3 June 2026. Open the linked bulletin for the product, severity and reference information published in that issue.

Official advisory ↗
CERT-FR · French · CERTFR-2026-AVI-0783Multiples vulnérabilités dans Microsoft Azure

S des avis Flux RSS des indicateurs de compromission Flux RSS des durcissement et recommandations Flux RSS des bulletins d'actualité Premier Ministre S.G.D.S.N Agence nationale de la sécurité des systèmes d'information Paris, le 19 juin 2026 N° CERTFR-2026-AVI-0783 Affaire suivie par: CERT-FR Avis du CERT-FR Objet: Multiples vulnérabilités dans Microsoft Azure Gestion du document Référence CERTFR-2026-AVI-0783 Titre Multiples vulnérabilités dans Microsoft Azure Date de la première version 19 juin 2026 Date de la dernière version 19 juin 2026 Source(s) Bulletin de sécurité Microsoft CVE-2026-8643 du 04 juin 2026 Bulletin de sécurité Microsoft CVE-2026-10275 du 05 juin 2026 Bulletin de sécurité Microsoft CVE-2026-46274 du 10 juin 2026 Bulletin de sécurité Microsoft CVE-2026-46280 du 10 juin 2026 Bulletin de sécurité Microsoft CVE-2026-46285 du 10 juin 2026 Bulletin de sécurité Microsoft CVE-2026-46287 du 10 juin 2026 Bulletin de sécurité Microsoft CVE-2026-46289 du 10 juin 2026 Bulletin de sécurité Microsoft CVE-2026-46291 du 10 juin 2026 Bulletin de sécurité Microsoft CVE-2026-46292 du 10 juin 2026 Bulletin de sécurité Microsoft CVE-2026-46293 du 10 juin 2026 Bulletin de sécurité Microsoft CVE-2026-46296 du 10 juin 2026 Bulletin de sécurité Microsoft CVE-2026-46299 du 10 juin 2026 Bulletin de s

Official advisory ↗
03

Patch and workaround

Operational remediation based on structured source evidence.

Status
?Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.
Fix availability varies by product
Affected
Fixed
An authoritative update reference is available, but the fixed version is not recorded in the structured CVE fields. Check the linked vendor advisory for the applicable release.
Action
Use the product-specific evidence above. Patch only products with a verified fixed release, and keep every affected or under-investigation state without a matching fix in the remediation queue.
Workaround
No verified workaround is recorded. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
04

Evidence and provenance

Published 1 Jun 2026 · Last source change 1 Jun 2026, 19:31 UTC · CWE-120 · Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

CVE recordCVE.org · 5.2
CVSS sourceCNA
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-08-14
European sourceENISA EUVD · EUVD-2026-33680
Product sourceVendor CSAF · SUSE Product Security Team
Remediation sourceVendor CSAF · SUSE Product Security Team
CWE sourceCNA
NVD statusNVD not scheduled

Missing structured fields: affected product. Missing data is not evidence of low risk; review the primary advisory.

Material change intelligence

What changed after publication

View recent updates ↗
  1. Remediation statusRemediation status changed from Awaiting fix to Mitigation available.
    Before
    Awaiting fix
    After
    Mitigation available
    SUSE Product Security Team ↗
Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
CVE published
Remediation guidance recorded
ENISA EUVD · EUVD-2026-33680↗SUSE Product Security Team security advisory↗CVE authority or vendor reference↗Official CVE record (CNA and ADP data)↗NVD record↗
Technical terms and abbreviations used in this report
CVE
Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS
Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS
Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE
Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA
CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP
Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD
National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT
A computer security incident response team that publishes warnings or coordinates incident response.
PoC
Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF
Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL
Living off the land: abuse of legitimate tools or system functions during an attack.
Free version - for non-commercial use only.CVE-2026-10275 · cve.blacktree.nl