How severe is CVE-2026-46638?

No CVSS score has been assigned to CVE-2026-46638 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by CVE-2026-46638?

CVE-2026-46638 affects the following packages: twig/twig (Packagist). Ecosystems affected: Packagist.

How do I fix CVE-2026-46638?

Update twig/twig to 3.26.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-46638 is resolved across your whole dependency graph.

How do I detect CVE-2026-46638 in my Packagist dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for twig/twig, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2026-46638 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

Is CVE-2026-46638 actively exploited in the wild?

No public exploit code has been indexed for CVE-2026-46638 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2026-46638?

CVE-2026-46638 has an EPSS (Exploit Prediction Scoring System) score of 0.5%, placing it in the 39th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2026-46638?

CVE-2026-46638 is classified as CWE-693 (CWE-693). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2026-46638 published, and has it been updated?

CVE-2026-46638 was published on July 14, 2026 and was last updated on August 12, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐘 Packagist

Not in CISA KEV

CVE-2026-46638 — twig/twig

Fix: twigphp/Twig@819c6a8

CVE-2026-46638 is a CWE-693 vulnerability in twig/twig. A fix is available for twig/twig — see the affected versions and patch details below.

Twig: `{% sandbox %}{% include %}` skips checkSecurity() on cached templates (incomplete fix for CVE-2024-45411)

Also known asGHSA-7fxw-r6jv-74c8

Published

Jul 14, 2026

Updated

Aug 12, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Oct 2, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for CVE-2026-46638.

EPSS Exploitation Probability

via FIRST.org ↗

0.5%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs39th percentile — riskier than 39% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

Real-World Exposure

1 pkg affected

🐘twig/twig

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.

Description

The fix for CVE-2024-45411 / GHSA-6j75-5wfj-gh66 added an explicit $loaded->unwrap()->checkSecurity() call in CoreExtension::include() so that a template already cached in Environment::$loadedTemplates is re-checked when included with sandboxed = true.

The deprecated but still functional {% sandbox %}{% include ... %}{% endsandbox %} tag path was not updated: it compiles to enableSandbox(); yield from $this->load(...)->unwrap()->yield(...); disableSandbox(); with no checkSecurity() re-invocation. If the included template was loaded once outside the sandbox in the same Environment instance, its constructor (and therefore its compiled checkSecurity() call) already ran while isSandboxed() was false, so the tags/filters/functions allowlist enforced by SecurityPolicy::checkSecurity() is never applied.

An attacker who can author the included template gains access to every filter, function and tag registered in the environment, regardless of the sandbox policy.

Resolution

The compiled output of {% sandbox %}{% include %} now calls checkSecurity() on the loaded template, matching the behaviour of CoreExtension::include() with sandboxed = true.

Credits

Twig would like to thank Claude Mythos Preview (via Project Glasswing) for reporting the issue and providing the fix.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐘Packagist	`twig/twig`	all versions	3.26.0`composer require twig/twig:^3.26.0`

Affected Products

1 product · 1 configurations

Application

twigsymfony

< 3.26.0

range

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for twig/twig, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update twig/twig to 3.26.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-46638 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

Frequently Asked Questions

### Description The fix for CVE-2024-45411 / GHSA-6j75-5wfj-gh66 added an explicit `$loaded->unwrap()->checkSecurity()` call in `CoreExtension::include()` so that a template already cached in `Environment::$loadedTemplates` is re-checked when included with `sandboxed = true`. The deprecated but still functional `{% sandbox %}{% include ... %}{% endsandbox %}` tag path was not updated: it compiles to `enableSandbox(); yield from $this->load(...)->unwrap()->yield(...); disableSandbox();` with no `checkSecurity()` re-invocation. If the included template was loaded once outside the sandbox in th

O3 Security · Impact-Aware SCA

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CVE-2026-46638 — twig/twig

Exploitation Status

No confirmed exploitation observed yet

EPSS Exploitation Probability

Real-World Exposure

Description

Description

Resolution

Credits

Affected Packages

Affected Products

Detection & mitigation playbook

Detect

Fix

Workarounds

Frequently Asked Questions

Is CVE-2026-46638 in your dependencies?