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SilverstripeApplication

CVE-2021-41559

MEDIUM · 6.5 CVSS v3.1 Published 2022-06-28
Fix available
A fix is available. Upgrade to 4.10.9 or later.
See remediation →
72/100
Remediation priority · Elevated
Remotely reachable No privileges

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
Silverstripe silverstripe/framework 4.8.1 has a quadratic blowup in Convert::xml2array() that enables a remote attack via a crafted XML document.

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

Silverstripe framework 4.8.1 contains a quadratic time complexity vulnerability in the Convert::xml2array() function. When processing XML documents, the function exhibits O(n²) behavior that can be triggered by a specially crafted XML document, causing excessive CPU consumption and leading to denial of service.

MitigationUpgrade silverstripe/framework to a patched version, or implement input validation and size limits on XML documents processed by Convert::xml2array() to prevent denial of service from maliciously crafted documents.

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
SilverstripeApplication
Affected:< 4.10.9

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

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/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. Locate the Silverstripe framework installation
    Identify the project directory containing the Silverstripe installation. Look for a composer.json file or the vendor/silverstripe directory.
    Affected if The silverstripe/framework package is present in the project
  2. Determine the installed framework version
    Check the composer.lock file or run 'composer show silverstripe/framework' to retrieve the exact version number installed.
    Affected if The installed version is lower than 4.10.9 (e.g., 4.8.1, 4.9.x, 4.10.0-4.10.8)
  3. Identify usage of Convert::xml2array()
    Search the codebase for calls to Convert::xml2array() or \SilverStripe\Core\Convert::xml2array() to determine if this function is being invoked.
    Affected if The function is called in the application code to process XML input
  4. Verify XML input processing is exposed
    Review application endpoints, API routes, or file upload handlers that accept or process XML documents. Check configuration files for any XML-related imports or transformations.
    Affected if User-supplied or external XML data is passed to Convert::xml2array() without size or complexity limits
  5. Confirm no input validation or limits are applied
    Inspect code that calls Convert::xml2array() to see if there are any checks on XML document size, depth, or node count before processing.
    Affected if No validation or size limits exist on XML documents before they are processed by Convert::xml2array()

You are affected if your installed silverstripe/framework version is below 4.10.9 AND your application uses Convert::xml2array() to process XML documents without imposing size or complexity constraints.

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 4.10.9 or later
Fixed in 4.10.9
Interim mitigation

Upgrade silverstripe/framework to a patched version, or implement input validation and size limits on XML documents processed by Convert::xml2array() to prevent denial of service from maliciously crafted documents.

Recommended fix High confidence

Silverstripe framework 4.10.9 or later

  1. 1. Identify the current Silverstripe framework version by checking your composer.json or running `composer show silverstripe/framework`
  2. 2. Upgrade the silverstripe/framework package to version 4.10.9 or later using `composer require silverstripe/framework:^4.10.9`
  3. 3. Run `composer update` to apply the changes
  4. 4. Clear any caches (delete the cache directory or run `php framework/scripts/cli-script.php dev/build?flush=1`)
  5. 5. Test the application to verify functionality remains intact
Caveat Review the Silverstripe 4.10.9 release notes for any breaking changes before upgrading in production environments

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

Fix this in Silverstripe Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing6.0 h
  • Review / QA2.0 h
20.0 hours of engineering $3,500
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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-2021-41559 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