OpenconnectApplication · Infradead

CVE-2012-6128

MEDIUM · 5.0 CVSS v2.0 Published 2013-02-24
Fix available
A fix is available. Upgrade to after 4.07 or later.
See remediation →
59/100
Remediation priority · Elevated
Remotely reachable No privileges 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
Multiple stack-based buffer overflows in http.c in OpenConnect before 4.08 allow remote VPN gateways to cause a denial of service (application crash) via a long (1) hostname, (2) path, or (3) cookie list in a response.

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 · moderate confidence

Stack-based buffer overflows in OpenConnect's http.c file before version 4.08 allow a malicious VPN gateway to send responses containing excessively long hostname, path, or cookie list values that overflow stack buffers, causing the application to crash.

MitigationUpgrade OpenConnect to version 4.08 or later to obtain the patched http.c code. Until then, limit connections to trusted VPN gateways only.

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
OpenconnectApplication
Affected:<= 4.07= 1.00= 1.10= 1.20= 1.30= 1.40= 2.00= 2.01= 2.10= 2.11= 2.12= 2.20

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
Authentication
None
Confidentiality
None
Integrity
None
Availability
Partial

AV:N/AC:L/Au:N/C:N/I:N/A:P

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. Verify OpenConnect is installed
    Run command: which openconnect or dpkg -l | grep openconnect or rpm -qa | grep openconnect
    Affected if OpenConnect is not found on the system, then not affected by this CVE
  2. Determine installed OpenConnect version
    Run command: openconnect --version
    Affected if Version output shows a number that matches the affected list: 1.00, 1.10, 1.20, 1.30, 1.40, 2.00, 2.01, 2.10, 2.11, 2.12, 2.20, or any version <= 4.07
  3. Confirm version is in vulnerable range
    Compare your installed version number to the list of affected versions (any version <= 4.07 or specifically listed versions)
    Affected if Installed version is 4.07 or lower, or matches any version in the affected list (1.00, 1.10, 1.20, 1.30, 1.40, 2.00, 2.01, 2.10, 2.11, 2.12, 2.20)
  4. Verify http.c is part of the installation
    Check for the OpenConnect binary or source installation: locate openconnect or find /usr -name '*openconnect*'
    Affected if OpenConnect is installed from source or package that includes the vulnerable http.c handling code

A user is affected if OpenConnect version 4.07 or lower (specifically versions 1.00 through 2.20 as listed) is installed and used to connect to VPN gateways, since the vulnerability triggers when processing server responses containing oversized hostname, path, or cookie values.

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 4.07
Interim mitigation

Upgrade OpenConnect to version 4.08 or later to obtain the patched http.c code. Until then, limit connections to trusted VPN gateways only.

Fix this in Openconnect Scoped from the published advisory
  • Consultation2.0 h
  • Implementation2.0 h
  • Testing3.0 h
  • Review / QA1.0 h
8.0 hours of engineering $1,390
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,224.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2012-6128 — 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-2012-6128 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