dbcve.org
RexmlApplication · Ruby Lang

CVE-2024-43398

MEDIUM · 5.9 CVSS v3.1 Published 2024-08-22
Fix available
A fix is available. Upgrade to 3.3.6 or later.
See remediation →
68/100
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
REXML is an XML toolkit for Ruby. The REXML gem before 3.3.6 has a DoS vulnerability when it parses an XML that has many deep elements that have same local name attributes. If you need to parse untrusted XMLs with tree parser API like REXML::Document.new, you may be impacted to this vulnerability. If you use other parser APIs such as stream parser API and SAX2 parser API, this vulnerability is not affected. The REXML gem 3.3.6 or later include the patch to fix the vulnerability.

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

A denial-of-service vulnerability in Ruby's REXML gem allows attackers to cause excessive resource consumption when parsing XML documents with deeply nested elements that share the same local name attributes. The vulnerability specifically affects the tree parser API (REXML::Document.new), while stream parser and SAX2 parser APIs are not impacted.

MitigationUpgrade the REXML gem to version 3.3.6 or later, or alternatively migrate to stream parser or SAX2 parser APIs if gem upgrades are not feasible in the environment.

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
RexmlApplication
Affected:< 3.3.6
Bootstrap OsOperating system
Affected:all versions

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
High
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.1/AV:N/AC:H/PR:N/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. Identify REXML gem version
    Run 'gem list rexml' to list the installed REXML gem version, or check the gemspec/Gemfile for the version specification
    Affected if The displayed version is lower than 3.3.6
  2. Locate REXML::Document.new usage
    Search codebase for 'REXML::Document.new' or 'Document.new' with 'require rexml/document' in the same file or loaded dependencies
    Affected if The application code uses REXML::Document.new (tree parser API) to parse XML input
  3. Confirm XML input contains nested elements
    Review the XML documents being parsed - check if they contain deeply nested elements with repeating local name attributes
    Affected if The parsed XML contains elements that are deeply nested AND share the same local name attributes at the same depth level
  4. Check NetApp Bootstrap OS environment
    Identify if the target system runs NetApp Bootstrap OS - check system information, product model, or firmware version
    Affected if The system is running NetApp Bootstrap OS of any version

You are affected if REXML gem version is below 3.3.6 AND your code uses REXML::Document.new to parse XML with deeply nested same-name elements, or if the system runs any version of NetApp Bootstrap OS.

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.

dbcve · scoped
Upgrade available Upgrade to 3.3.6 or later
Fixed in 3.3.6
Interim mitigation

Upgrade the REXML gem to version 3.3.6 or later, or alternatively migrate to stream parser or SAX2 parser APIs if gem upgrades are not feasible in the environment.

Recommended fix High confidence

REXML gem 3.3.6 or later

  1. 1. Identify the current version of the Rexml gem in your Ruby environment by running `gem list rexml`
  2. 2. Update the Rexml gem to version 3.3.6 or later using `gem install rexml -v '>= 3.3.6'` or add to your Gemfile with `gem 'rexml', '>= 3.3.6'`
  3. 3. Run `bundle update rexml` to update the gem in your project dependencies
  4. 4. Verify the installed version is 3.3.6 or later with `gem list rexml`
  5. 5. Test your application to ensure XML parsing functionality works correctly after the upgrade

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Rexml Scoped from the published advisory
  • Consultation1.0 h
  • Implementation1.0 h
  • Testing2.0 h
  • Review / QA1.0 h
5.0 hours of engineering $860
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,376.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2024-43398 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

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-2024-43398 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

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