OpenvpnApplication

CVE-2017-7479

MEDIUM · 6.5 CVSS v3.0 Published 2017-05-15
Fix available
A fix is available. Upgrade to after 2.3.14 or later.
See remediation →
71/100
Remediation priority · Elevated
Remotely reachable Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
OpenVPN versions before 2.3.15 and before 2.4.2 are vulnerable to reachable assertion when packet-ID counter rolls over resulting into Denial of Service of server by authenticated attacker.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

OpenVPN versions before 2.3.15 and before 2.4.2 contain a reachable assertion vulnerability triggered when the packet-ID counter rolls over during a replay attack by an authenticated remote attacker, causing the VPN server to crash and resulting in denial of service.

MitigationUpgrade OpenVPN to version 2.3.15 or later (2.3.x branch) or version 2.4.2 or later (2.4.x branch) to remediate this vulnerability.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
OpenvpnApplication
Affected:<= 2.3.14= 2.4.0= 2.4.1

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Determine installed OpenVPN version
    Run 'openvpn --version' or check package manager (dpkg -l openvpn / rpm -qi openvpn)
    Affected if Version is 2.3.14 or earlier, 2.4.0, or 2.4.1
  2. Confirm OpenVPN is running as a server
    Check running processes for 'openvpn --server' or review OpenVPN configuration file for 'mode server' or 'tls-server' directive
    Affected if OpenVPN is running in server mode (vulnerability only affects server configurations)
  3. Verify OpenVPN service is exposed to remote clients
    Review firewall rules and OpenVPN bind address in configuration to confirm the server listens on accessible network interfaces
    Affected if Server is network-accessible to remote authenticated clients (required for remote attack vector)
  4. Monitor for unexpected server crashes
    Review system logs (journalctl -u openvpn, /var/log/messages, or /var/log/openvpn.log) for assertion failures or sudden service restarts
    Affected if Server exhibits unexplained crashes, which may indicate exploitation attempts

You are affected if OpenVPN server version is 2.3.14 or earlier, 2.4.0, or 2.4.1 and the service is running in server mode accessible to remote clients.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Upgrade available Upgrade to a release after 2.3.14
Interim mitigation

Upgrade OpenVPN to version 2.3.15 or later (2.3.x branch) or version 2.4.2 or later (2.4.x branch) to remediate this vulnerability.

Fix this in Openvpn Scoped from the published advisory
  • Consultation2.0 h
  • Implementation2.0 h
  • Testing4.0 h
  • Review / QA2.0 h
10.0 hours of engineering $1,720
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,752.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2017-7479 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2017-7479 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data