BlackTreeCVE Intelligence
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Full vulnerability report · 2026
CVE-2026-40215High confidence

OpenVPN — Out-of-bounds Read

OpenVPN · OpenVPN

6.1MediumCVSS 4.0
Recommended action
Scheduled

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.

Patch available
R
Operational reassessment

Published severity in operational context

Open reassessment dashboard →
Published severityMediumOperational priority:Medium, unchanged from published severity.unchanged

Evidence used

  • No CISA KEV confirmation is currently recorded.
  • EPSS is 0.59% 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 OpenVPN OpenVPN 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: As exposure requiresRemediation target: Within 365 days

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.

Distribution package intelligence

Release-specific package status

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

8 package states
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
Alpine v3.23v3.23 · mainopenvpnVendor fix publishedAlpine records a security fix at this version. An absent entry does not mean the package is unaffected.2.6.20-r0Alpine Security Database ↗Source updated 3 Oct 2026
Alpine v3.22v3.22 · mainopenvpnVendor fix publishedAlpine records a security fix at this version. An absent entry does not mean the package is unaffected.2.6.20-r0Alpine Security Database ↗Source updated 3 Oct 2026
Alpine v3.21v3.21 · mainopenvpnVendor fix publishedAlpine records a security fix at this version. An absent entry does not mean the package is unaffected.2.6.20-r0Alpine Security Database ↗Source updated 3 Oct 2026
Debian trixietrixie · sourceopenvpnVendor fix publishedDebian records a fixed source-package version for this release.2.6.14-1+deb13u2Debian Security Tracker ↗Source updated 5 Oct 2026
Debian bookwormbookworm · sourceopenvpnVendor fix publishedDebian records a fixed source-package version for this release.2.6.14-0+deb12u1Debian Security Tracker ↗Source updated 5 Oct 2026
Debian forkyforky · sourceopenvpnVendor fix publishedDebian records a fixed source-package version for this release.2.7.2-1Debian Security Tracker ↗Source updated 5 Oct 2026
Debian sidsid · sourceopenvpnVendor fix publishedDebian records a fixed source-package version for this release.2.7.2-1Debian Security Tracker ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archiveopenvpnVendor fix publishedCanonical reports that a fixed source package version has been published. Repository candidate availability is not checked by BlackTree.2.6.19-0ubuntu0.24.04.2Canonical Ubuntu Security ↗Source updated 5 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-2026-40215 · CSAF 2.0 · revision 5 · interimSUSE Product Security TeamCVE-2026-40215
9 known affected

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

  • openvpn as component of SUSE Linux Enterprise Server 16.0
  • openvpn-auth-pam-plugin as component of SUSE Linux Enterprise Server 16.0
  • openvpn-devel as component of SUSE Linux Enterprise Server 16.0
  • openvpn-down-root-plugin as component of SUSE Linux Enterprise Server 16.0
  • openvpn as component of SUSE Linux Enterprise Server for SAP applications 16.0
  • openvpn-auth-pam-plugin as component of SUSE Linux Enterprise Server for SAP applications 16.0
  • openvpn-devel as component of SUSE Linux Enterprise Server for SAP applications 16.0
  • openvpn-down-root-plugin as component of SUSE Linux Enterprise Server for SAP applications 16.0
  • openvpn as component of openSUSE Leap 16.0
Summary
A race condition in OpenVPN 2.6.0 through 2.6.19 and 2.7_alpha1 through 2.7.1 allows remote attackers to potentially cause a server crash or leak heap memory via a use-after-free triggered during TLS session promotion.
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-2026-35200

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 actionScheduled

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.

Patch available
01

What, why and how

A race condition in OpenVPN 2.6.0 through 2.6.19 and 2.7_alpha1 through 2.7.1 allows remote attackers to potentially cause a server crash or leak heap memory via a use-after-free triggered during TLS session promotion.

What

A race condition in OpenVPN 2.6.0 through 2.6.19 and 2.7_alpha1 through 2.7.1 allows remote attackers to potentially cause a server crash or leak heap memory via a use-after-free triggered during TLS session promotion.

Why

The product reads data past the end, or before the beginning, of the intended buffer.

How

An attacker operating through a network path may attempt exploitation with low privileges. If successful, the issue may disrupt the affected service.

What

A race condition in OpenVPN 2.6.0 through 2.6.19 and 2.7_alpha1 through 2.7.1 allows remote attackers to potentially cause a server crash or leak heap memory via a use-after-free triggered during TLS session promotion.

Why

The product reads data past the end, or before the beginning, of the intended buffer.

How

An attacker operating through a network path may attempt exploitation with low privileges. If successful, the issue may disrupt the affected service.

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 → Out-of-bounds Read → disrupt the affected service
Attack surface
Network
Privileges required
Low: a basic authenticated account is required
User interaction
None
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-125 ↗

CWE-125: Out-of-bounds Read. The product reads data past the end, or before the beginning, of the intended 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:L/UI:N/VC:H/VI:N/VA:H/SC:L/SI:N/SA:L

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.PRLowPrivileges required: The attacker needs basic user-level privileges.UINoneUser interaction: No action by another user is required.VCHighVulnerable-system confidentiality: A successful attack can cause a major loss.VINoneVulnerable-system integrity: No direct loss is represented by this metric.VAHighVulnerable-system availability: A successful attack can cause a major loss.SCLowSubsequent-system confidentiality: A successful attack can cause a limited loss.SINoneSubsequent-system integrity: No direct loss is represented by this metric.SALowSubsequent-system availability: A successful attack can cause a limited loss.
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.
NetworkDenial of serviceCWE-125
A

Official authority intelligence

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

BSI · German · WID-SEC-2026-1264OpenVPN: Mehrere Schwachstellen

Ein Angreifer kann mehrere Schwachstellen in OpenVPN ausnutzen, um einen Denial of Service Angriff durchzuführen, und um Informationen offenzulegen.

Official advisory ↗
Cyber Security Agency of Singapore · English · CSA-SB-20260610Security Bulletin 10 Jun 2026

The Cyber Security Agency of Singapore included this CVE in its official Security Bulletin 10 Jun 2026, published on 10 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-1021Multiples vulnérabilités dans Stormshield Network Security

De multiples vulnérabilités ont été découvertes dans Stormshield Network Security. Certaines d'entre elles permettent à un attaquant de provoquer une exécution de code arbitraire à distance, un déni de service à distance et une atteinte à la confidentialité des données.

Official advisory ↗
JVN iPedia · Japanese · JVNDB-2026-027938OpenVPN TechnologiesのOpenVPNにおける複数の脆弱性

OpenVPN 2.6.0から2.6.19および2.7_alpha1から2.7.1における競合状態によって、リモートの攻撃者がTLSセッション昇格中に発生するUse-After-Freeを利用し、サーバークラッシュを引き起こしたりヒープメモリを漏洩させたりする可能性があります。

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.
Patch available
Affected
Fixed
No fixed version is explicitly recorded in the structured CVE data.
Action
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
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 8 Jun 2026 · Last source change 16 Jun 2026, 12:24 UTC · CWE-125 · Out-of-bounds Read

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-2026-35200
Product sourceVendor CSAF · SUSE Product Security Team
Remediation sourceVendor CSAF · SUSE Product Security Team
CWE sourceCNA
NVD statusNVD enriched

Core structured fields are present and their contributing authorities are shown above.

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-2026-35200↗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-2026-40215 · cve.blacktree.nl