dbcve.org
SymfonyFramework / library · Sensiolabs

CVE-2026-47767

CRITICAL · 9.8 CVSS v3.1 Published 2026-07-14
Fix available
A fix is available. Upgrade to 5.4.52 / 6.4.40 or later.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click 5 weeks old

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
Symfony is a PHP framework for web and console applications and a set of reusable PHP components. From 5.4.46 until 5.4.52, 6.4.40, 7.4.12, and 8.0.12, the CVE-2024-50340 fix gated runtime argv parsing on empty($_GET), but parse_str() and the web SAPI can disagree, allowing a crafted query string to leave $_GET empty while $_SERVER['argv'] still carries attacker-controlled --env or --no-debug flags that change APP_ENV or APP_DEBUG. This issue is fixed in versions 5.4.52, 6.4.40, 7.4.12, and 8.0.12.

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

Symfony's runtime argv parsing can be manipulated via a crafted query string that leaves $_GET empty while populating $_SERVER['argv'] with attacker-controlled --env or --no-debug flags, enabling modification of APP_ENV and APP_DEBUG settings to change application behavior.

MitigationUpgrade Symfony to versions 5.4.52, 6.4.40, 7.4.12, or 8.0.12 to apply the fix that properly gates argv parsing.

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
SymfonyFramework / library
Affected:>= 5.4.46, < 5.4.52>= 6.4.14, < 6.4.40>= 7.1.7, < 7.4.12>= 8.0.0, < 8.0.12

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
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/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 installed Symfony version
    Run 'composer show sensiolabs/symfony-packagename' or inspect the version in your composer.lock file under the 'sensiolabs/symfony-package' or 'symfony/symfony' entry
    Affected if The version falls within 5.4.46 to 5.4.51, 6.4.14 to 6.4.39, 7.1.7 to 7.4.11, or 8.0.0 to 8.0.11
  2. Confirm Symfony runtime component usage
    Check if your application bootstrap or public/index.php loads Symfony's Dotenv component or uses Symfony's runtime by inspecting your autoload files, bootstrap configuration, or the Dotenv class instantiation in your codebase
    Affected if The application loads and processes environment variables through Symfony's Dotenv component in a web request context
  3. Verify argv processing in web context
    Create a test script that outputs $_SERVER['argv'] when accessed via HTTP with a query string (e.g., '?test=value'), then inspect whether arguments appear in this superglobal
    Affected if Query string parameters cause $_SERVER['argv'] to be populated while $_GET remains empty, allowing argv injection
  4. Test APP_ENV and APP_DEBUG manipulation
    Make an HTTP request with a crafted query string containing --env=production or --no-debug flags and observe whether the application's environment or debug settings change from their configured defaults
    Affected if Passing --env or --no-debug via query string modifies the effective APP_ENV or APP_DEBUG values used by the application

Your environment is affected if the Symfony version is within the affected ranges and your application processes command-line arguments through Symfony's runtime/Dotenv component in web requests, allowing $_SERVER['argv'] to be populated via query strings.

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 5.4.52 / 6.4.40 / 7.4.12 or later
Fixed in 5.4.526.4.407.4.12
Interim mitigation

Upgrade Symfony to versions 5.4.52, 6.4.40, 7.4.12, or 8.0.12 to apply the fix that properly gates argv parsing.

Recommended fix High confidence

Upgrade to Symfony 5.4.52, 6.4.40, 7.4.12, or 8.0.12 (choose the appropriate branch for your project)

  1. Run `composer require symfony/framework-bundle:^5.4.52` to upgrade to the fixed 5.4.x version
  2. OR run `composer require symfony/framework-bundle:^6.4.40` to upgrade to the fixed 6.4.x version
  3. OR run `composer require symfony/framework-bundle:^7.4.12` to upgrade to the fixed 7.4.x version
  4. OR run `composer require symfony/framework-bundle:^8.0.12` to upgrade to the fixed 8.0.x version
  5. Run `composer update symfony/framework-bundle` to apply the upgrade
  6. Verify the upgrade succeeded by checking `composer show symfony/framework-bundle | grep version`
Caveat Minor version upgrades within the same major version typically have no breaking changes; however, review the Symfony CHANGELOG for any deprecation notices between your current and target version

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

Fix this in Symfony Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing6.0 h
  • Review / QA3.0 h
15.0 hours of engineering $2,560
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $4,096.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2026-47767 — 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-2026-47767 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