BlackTreeCVE Intelligence
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Full vulnerability report · 2023
CVE-2023-46850High confidence

Use after free in OpenVPN version 2.6.0 to 2.6.6 may lead to undefined behavoir, leaking memory buffers or remote execution when sending network buffers to a remote peer

OpenVPN · OpenVPN 2 (Community)

Official source article: Siemens SSA-417159 ↗. Check the applicable product and release in the original source.

9.8CriticalCVSS 3.1
Recommended action
Patch only the product branches with a verified fix

Critical technical impact with a remotely reachable, unauthenticated path; no CISA KEV confirmation is currently recorded. Verified remediation exists for at least one product or source, but 1 structured product or package state 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 severityCriticalOperational priority:Critical, unchanged from published severity.unchanged

Evidence used

  • No CISA KEV confirmation is currently recorded.
  • The selected CVSS metric records a network-reachable, unauthenticated path with no user interaction.
  • EPSS is 2.00% 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 2 (Community) 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: Within 3 daysRemediation target: Within 90 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.

Cross-source reconciliation

Remediation availability differs by product scope

Verified remediation exists for at least one product or source, but 1 structured product or package state remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Distribution package intelligence

Release-specific package status

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

7 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.2.6.7-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.2.6.7-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.2.6.7-r0Alpine Security Database ↗Source updated 3 Oct 2026
Debian trixietrixie · sourceopenvpnVendor fix publishedDebian records a fixed source-package version for this release.2.6.7-1Debian Security Tracker ↗Source updated 5 Oct 2026
Debian bookwormbookworm · sourceopenvpnVendor fix publishedDebian records a fixed source-package version for this release.2.6.3-1+deb12u2Debian Security Tracker ↗Source updated 5 Oct 2026
Debian forkyforky · sourceopenvpnVendor fix publishedDebian records a fixed source-package version for this release.2.6.7-1Debian Security Tracker ↗Source updated 5 Oct 2026
Debian sidsid · sourceopenvpnVendor fix publishedDebian records a fixed source-package version for this release.2.6.7-1Debian Security Tracker ↗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
SSA-417159 · CSAF 2.0 · revision 1 · interimSiemens ProductCERTSSA-417159: Multiple Vulnerabilities in SINEMA Remote Connect Client Before V3.2 SP2
1 known affected

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

  • SINEMA Remote Connect Client
Summary
Use after free in OpenVPN version 2.6.0 to 2.6.6 may lead to undefined behavoir, leaking memory buffers or remote execution when sending network buffers to a remote peer.
Remediation
Update to V3.2 SP2 or later version
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-2023-51016

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

Critical technical impact with a remotely reachable, unauthenticated path; no CISA KEV confirmation is currently recorded. Verified remediation exists for at least one product or source, but 1 structured product or package state remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Fix availability varies by product
01

What, why and how

Use after free in OpenVPN version 2.6.0 to 2.6.6 may lead to undefined behavoir, leaking memory buffers or remote execution when sending network buffers to a remote peer.

What

Use after free in OpenVPN version 2.6.0 to 2.6.6 may lead to undefined behavoir, leaking memory buffers or remote execution when sending network buffers to a remote peer.

Why

The program can continue using memory after it has been released, producing unsafe and attacker-influenceable behaviour.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

What

Use after free in OpenVPN version 2.6.0 to 2.6.6 may lead to undefined behavoir, leaking memory buffers or remote execution when sending network buffers to a remote peer.

Why

The program can continue using memory after it has been released, producing unsafe and attacker-influenceable behaviour.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. 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 → Use After Free → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Network
Privileges required
None: unauthenticated exploitation is possible
User interaction
None
Attack complexity
Low: no specialised conditions are recorded
Security boundary
Unchanged: impact remains within the vulnerable component's security authority
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-416 ↗

CWE-416: Use After Free. The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Common Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.

AVNetworkAttack vector: The vulnerable component can be reached over a network.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRNonePrivileges required: The attacker does not need an account or existing privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CHighConfidentiality impact: A successful attack can cause a major loss.IHighIntegrity impact: A successful attack can cause a major loss.AHighAvailability impact: A successful attack can cause a major 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.
NetworkUnauthenticatedCWE-416
A

Official authority intelligence

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

BSI · German · WID-SEC-2023-2872OpenVPN: Mehrere Schwachstellen

Ein entfernter authentifizierter Angreifer kann mehrere Schwachstellen in OpenVPN ausnutzen, um einen Denial-of-Service-Zustand zu erzeugen oder vertrauliche Informationen offenzulegen.

Official advisory ↗
Cyber Security Agency of Singapore · English · CSA-SB-20231115Security Bulletin 15 Nov 2023

The Cyber Security Agency of Singapore included this CVE in its official Security Bulletin 15 Nov 2023, published on 15 November 2023. Open the linked bulletin for the product, severity and reference information published in that issue.

Official advisory ↗
CERT-FR · French · CERTFR-2024-AVI-0113Multiples vulnérabilités dans les produits IBM

d?id=CVE-2023-34455 Référence CVE CVE-2023-34462 https://www.cve.org/CVERecord?id=CVE-2023-34462 Référence CVE CVE-2023-36478 https://www.cve.org/CVERecord?id=CVE-2023-36478 Référence CVE CVE-2023-36479 https://www.cve.org/CVERecord?id=CVE-2023-36479 Référence CVE CVE-2023-40167 https://www.cve.org/CVERecord?id=CVE-2023-40167 Référence CVE CVE-2023-41900 https://www.cve.org/CVERecord?id=CVE-2023-41900 Référence CVE CVE-2023-44487 https://www.cve.org/CVERecord?id=CVE-2023-44487 Référence CVE CVE-2023-46308 https://www.cve.org/CVERecord?id=CVE-2023-46308 Référence CVE CVE-2023-46849 https://www.cve.org/CVERecord?id=CVE-2023-46849 Référence CVE CVE-2023-46850 https://www.cve.org/CVERecord?id=CVE-2023-46850 Référence CVE CVE-2023-4807 https://www.cve.org/CVERecord?id=CVE-2023-4807 Référence CVE CVE-2023-5363 https://www.cve.org/CVERecord?id=CVE-2023-5363 Référence CVE CVE-2023-5676 https://www.cve.org/CVERecord?id=CVE-2023-5676 Gestion détaillée du document le 09 février 2024 Version initiale Alertes Avis Bulletins d’actualités Mentions légales Conditions générales À propos Contact cyber.gouv.fr service-public.fr legifrance.gouv.fr info.gouv.fr france.fr info.gouv.fr/risques Premier Ministre / Secrétariat Général de la Défense et de la Sécurité Nationale / Agence nationale de la sécurité des systè

Official advisory ↗
JVN iPedia · Japanese · JVNDB-2023-017884OpenVPN Technologies の OpenVPN 等複数ベンダの製品における解放済みメモリの使用に関する脆弱性

OpenVPN Technologies の OpenVPN 等複数ベンダの製品には、解放済みメモリの使用に関する脆弱性が存在します。

Official advisory ↗
JVN iPedia · Japanese · JVNDB-2023-026339OpenVPN Technologies の OpenVPN 等複数ベンダの製品におけるゼロ除算に関する脆弱性

OpenVPN Technologies の OpenVPN 等複数ベンダの製品には、ゼロ除算に関する脆弱性が存在します。

Official advisory ↗
NCSC-NL · Dutch · NCSC-2024-0362Kwetsbaarheden verholpen in Siemens producten

De kwetsbaarheden stellen een kwaadwillende mogelijk in staat aanvallen uit te voeren die kunnen leiden tot de volgende categorieën schade: - Denial-of-Service (DoS) - Manipulatie van gegevens - Omzeilen van een beveiligingsmaatregel - Omzeilen van authenticatie - (Remote) code execution (Administrator/Root rechten) - (Remote) code execution (Gebruikersrechten) - Toegang tot systeemgegevens - Verhoogde gebruikersrechten De kwaadwillende heeft hiervoor toegang nodig tot de productieomgeving. Het is goed gebruik een dergelijke omgeving niet publiek toegankelijk te hebben.

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
SINEMA Remote Connect Client
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 11 Nov 2023 · Last source change 23 Jun 2026, 21:24 UTC · CWE-416 · Use After Free

CVE recordCVE.org · 5.2
CVSS sourceNIST NVD
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-2023-51016
Product sourceVendor CSAF · Siemens ProductCERT
Remediation sourceVendor CSAF · Siemens ProductCERT
CWE sourceCNA
NVD statusNVD modified after enrichment

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

Material change intelligence

What changed after publication

View recent updates ↗

No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.

Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
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-2023-46850 · cve.blacktree.nl