RailsApplication · Rubyonrails
CVE-2016-6316
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 · uneditedCross-site scripting (XSS) vulnerability in Action View in Ruby on Rails 3.x before 3.2.22.3, 4.x before 4.2.7.1, and 5.x before 5.0.0.1 might allow remote attackers to inject arbitrary web script or HTML via text declared as "HTML safe" and used as attribute values in tag handlers.
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 confidenceCross-site scripting vulnerability in Ruby on Rails Action View where text marked as 'HTML safe' can inject arbitrary HTML/script when used as attribute values in tag handlers. This occurs because the framework fails to escape content in attribute contexts even when marked as safe.
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
RailsApplication
= 3.0.0= 3.0.1= 3.0.2= 3.0.3= 3.0.4= 3.0.5= 3.0.6= 3.0.7= 3.0.8= 3.0.9= 3.0.10= 3.0.11
Ruby On RailsApplication
= 3.0.4= 3.2.14= 3.2.15= 3.2.19= 3.2.20= 3.2.22= 3.2.22.1= 4.0.10= 4.0.11= 4.0.11.1= 4.0.12= 4.0.13
Debian LinuxOperating system
= 8.0CVSS 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
- None
- User interaction
- Required
- Scope
- Changed
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
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 checksWork through these to decide whether this CVE applies to you.
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Identify installed Rails versionRun `rails --version` in the application root directory, or check the Gemfile.lock for the Rails gem version, or run `gem list rails`Affected if The installed Rails version is 3.0.0-3.0.11, 3.2.14-3.2.22.1, or 4.0.10-4.0.13
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Search for .html_safe usage in codebaseRun `grep -r "\.html_safe" app/` or search in your codebase for instances of `.html_safe` method calls in views and controllersAffected if The application uses `.html_safe` to mark content as safe HTML
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Check if html_safe content is used in tag attributesReview all `.html_safe` usages found and examine view templates (erb files) to see if the safe-marked content is passed as values to HTML tag attributes (e.g., `<tag attr="<%= some_var.html_safe %>">`)Affected if Content marked with `.html_safe` is being used inside HTML attribute values in ERB templates
You are affected if your Rails version is within the affected ranges AND your application uses `.html_safe` to mark content that is then rendered inside HTML tag attribute values in templates.
Generated from the published advisory. Verify against your own configuration.
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 dataUpgrade Ruby on Rails to version 3.2.22.3+, 4.2.7.1+, or 5.0.0.1+ to patch the Action View component. Review all uses of .html_safe in templates and ensure attribute values are properly escaped.
Fix this in Rails
Scoped from the published advisory
- Consultation2.0 h
- Implementation4.0 h
- Testing8.0 h
- Review / QA4.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $4,864.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2016-6316 — 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 sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2016-6316 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Version or environment caveats, and links to real fixes
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