dbcve.org
TwigFramework / library · Symfony

CVE-2026-46629

MEDIUM · 6.5 CVSS v3.1 Published 2026-07-14
Fix available
A fix is available. Upgrade to 3.26.0 or later.
See remediation →
71/100
Remediation priority · Elevated
Remotely reachable 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
Twig is a template language for PHP. Prior to 3.26.0, twig/intl-extra memoises IntlDateFormatter and NumberFormatter instances in arrays keyed by template-controlled filter arguments such as locale, pattern, and attrs, allowing a template to allocate many ICU formatter objects that remain pinned for the lifetime of the Twig\Environment. This issue is fixed in version 3.26.0.

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

Twig's intl-extra package implements flawed memoization for IntlDateFormatter and NumberFormatter instances, using template-controlled arguments (locale, pattern, attrs) as array keys. Attackers can craft templates that continuously allocate new ICU formatter objects, which remain pinned in memory for the Twig\Environment's entire lifetime, leading to memory exhaustion.

MitigationUpgrade Twig to version 3.26.0 or later which fixes the improper memoization logic that allowed unbounded ICU formatter object allocation.

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
TwigFramework / library
Affected:< 3.26.0

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

CVSS:3.1/AV:N/AC:L/PR:L/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. Check installed Twig version
    Run 'composer show symfony/twig-bridge' or 'composer show symfony/twig-pack' and note the version number, or inspect your composer.lock file for the twig-bridge or twig version
    Affected if The version is below 3.26.0
  2. Verify intl-extra package presence
    Run 'composer show symfony/intl-extra' or check your composer.lock for the intl-extra package entry
    Affected if The intl-extra package is installed in the project
  3. Confirm IntlDateFormatter or NumberFormatter usage in templates
    Search template files (*.html.twig) for calls to '\Twig\Extra\Intl\IntlDateFormatter' or '\Twig\Extra\Intl\NumberFormatter' or their filter equivalents like 'intl_date' or 'number_format'
    Affected if Templates use these ICU formatters with user-influenced locale, pattern, or attrs parameters
  4. Assess template input source
    Examine if the application accepts templates from untrusted sources, such as user-provided template content, database-stored templates, or template overrides from external input
    Affected if Untrusted or attacker-controlled template content can be rendered through the Twig environment

You are affected if you are running Twig version below 3.26.0 with the intl-extra package, and untrusted template content can be processed to inject varying locale, pattern, or attrs values into IntlDateFormatter or NumberFormatter calls.

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 3.26.0 or later
Fixed in 3.26.0
Interim mitigation

Upgrade Twig to version 3.26.0 or later which fixes the improper memoization logic that allowed unbounded ICU formatter object allocation.

Recommended fix High confidence

3.26.0

  1. Identify the project dependency file (composer.json)
  2. Update the twig/twig package version constraint to ^3.26.0 or ~3.26.0
  3. Run `composer update twig/twig` to fetch the fixed version
  4. Verify the installation by checking composer.lock for version 3.26.0
  5. Run tests to ensure the upgrade does not break existing functionality
Caveat Review the Twig 3.26.0 changelog for any breaking changes before upgrading

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

Fix this in Twig 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-2026-46629 — 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-2026-46629 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