CVE-2026-46634

Twig: `template_from_string()` escapes a SourcePolicy-driven sandbox via synthesized template name

Published Jul 14, 2026 CVSS 4.0 · 7.7 High EPSS < 1% KEV · Not listed

Description

Twig is a template language for PHP. From 3.9.0 until 3.26.0, template_from_string() compiles an inner template under a synthesized __string_template__<hash> name that can fall outside a SourcePolicyInterface sandbox decision, allowing a sandboxed template that can call template_from_string and include to render an inner template without security policy enforcement. This issue is fixed in version 3.26.0.

Analysis

Technical impact

Affected Systems

The vendor/product is Twig from twigphp. Affected versions are all releases from 3.9.0 up through 3.26.0, inclusive. These versions expose the sandbox escape via template_from_string.

Risk and Exploitability

The CVSS score is 7.7, indicating a high severity. The EPSS score is less than 1 %, suggesting a low likelihood of exploitation in the near term. The vulnerability is not listed in CISA’s KEV catalog. Based on the description, the likely attack vector requires the ability to supply or influence the template content, after which the attacker can trigger template_from_string to render an inner template outside the defined policy.

Affected Products

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

twigphp

Twig

affected

Version	Status	Constraints
`>= 3.9.0, < 3.26.0`	affected	—

Configuration 1 [-]

cpe:2.3:a:symfony:twig:*:*:*:*:*:*:*:*

No data.

Vendor Product Versions

Twigphp

Twig

Version	Status	Scheme	Platform
`[3.9.0,3.26.0)`	affected	semver	—

Remediation

No solution or workaround provided in the CVE record.

OpenCVE Recommended Actions

Upgrade Twig to version 3.26.0 or later to apply the patch that removes the legacy template_from_string behavior.
Verify that the application does not create templates from untrusted input or call template_from_string from within sandboxed templates; refactor code to avoid dynamic template compilation.
If an upgrade cannot be performed immediately, enforce a strict whitelist of allowed template names and disable the inclusion of dynamically generated templates, or remove the sandbox policy for known safe templates.

Generated by OpenCVE AI on July 31, 2026 at 04:36 UTC.

Tracking

Advisories

Source	ID	Title
Debian DSA	DSA-6311-1	php-twig security update
Github GHSA	GHSA-24x9-r6q4-q93w	Twig: `template_from_string()` escapes a SourcePolicy-driven sandbox via synthesized template name

Metrics

Attack Vector Network

Attack Complexity Low

Privileges Required Low

Attack Requirements Present

User Interaction None

Vulnerable System Confidentiality Impact High

Vulnerable System Integrity Impact High

Vulnerable System Availability Impact High

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact High

Integrity Impact High

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploit prediction score: < 1% (0.616% probability within 30 days)

Exploitation none

Automatable no

Technical Impact total

References

Link	Providers
https://github.com/twigphp/Twig/commit/1cde8f2b62463f85d47995fc25f8241cb409d915
https://github.com/twigphp/Twig/releases/tag/v3.26.0
https://github.com/twigphp/Twig/security/advisories/GHSA-24x9-r6q4-q93w

History

Jul 29, 2026 7:30 PM Scoring metrics updated View changes

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}`

Jul 15, 2026 3:15 PM First appearance in the feed. Affected vendors updated View changes

Type	Values Removed	Values Added
First Time appeared		Twigphp Twigphp twig
Vendors & Products		Twigphp Twigphp twig

Jul 14, 2026 9:45 PM Description updated. Title updated. Weaknesses updated. Added references. Scoring metrics updated View changes

Type	Values Removed	Values Added
Description		Twig is a template language for PHP. From 3.9.0 until 3.26.0, template_from_string() compiles an inner template under a synthesized __string_template__<hash> name that can fall outside a SourcePolicyInterface sandbox decision, allowing a sandboxed template that can call template_from_string and include to render an inner template without security policy enforcement. This issue is fixed in version 3.26.0.
Title		Twig: `template_from_string()` escapes a SourcePolicy-driven sandbox via synthesized template name
Weaknesses		CWE-693
References		https://github.com/twigphp/Twig/commit/1cde8f2b62463f85d47995fc25f8241cb409d915 https://github.com/twigphp/Twig/releases/tag/v3.26.0 https://github.com/twigphp/Twig/security/advisories/GHSA-24x9-r6q4-q93w
Metrics		cvssV4_0 `{'score': 7.7, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N'}`