high CVSS 8.8

CVE-2026-46640·PHP vulnerability

Twig is a template language for PHP. From 3.15.0 until 3.26.0, _self.(<string>) and import-alias dynamic attribute syntax can concatenate an attacker-controlled string into a MacroReferenceExpression name without identifier validation, causing raw PHP to be emitted into the generated template source and executed at template-load time. This issue is fixed in version 3.26.0.

Severity
high
Software
PHP
Fixed in
3.26.0
Published
2026-07-14

Affected versions

From: 3.15.0

Until: 3.26.0

Fixed in: 3.26.0

How to fix this CVE

Update PHP and the Twig template engine to version 3.26.0 or later to remediate this critical template injection vulnerability. The vulnerability allows authenticated attackers to inject arbitrary PHP code through dynamic attribute syntax in Twig macros, which executes during template compilation rather than runtime. Immediately patch all affected systems and review template files for suspicious macro references or import aliases.

sudo dnf update php php-twig

Defensia detects this vulnerability

How to check if you are affected

  1. Step 1: Check installed Twig version: php -r "echo Twig\\Environment::VERSION;" or composer show symfony/twig-bundle | grep Version
  2. Step 2: Verify if Twig is actively used in your PHP application by searching for .twig template files: find /var/www -name '*.twig' -type f | head -20
  3. Step 3: Search application logs and PHP error logs for compilation errors or warnings related to macro expressions: grep -i 'macro\|_self\.' /var/log/php-fpm/error.log | grep -v 'DEBUG'
  4. Step 4: Confirm the patch by running php -r "echo Twig\\Environment::VERSION;" and verify the version is 3.26.0 or higher

FAQ

What is CVE-2026-46640?

CVE-2026-46640 is a code injection vulnerability in Twig's template engine affecting versions 3.15.0 through 3.25.x. Attackers with authentication credentials can exploit dynamic attribute syntax in macros to inject raw PHP code that executes at template compilation time, leading to remote code execution.

Is CVE-2026-46640 being actively exploited?

No, this vulnerability is not currently listed on the CISA Known Exploited Vulnerabilities catalog, and no public exploits are available. However, the high CVSS score of 8.8 and the nature of the vulnerability warrant immediate patching.

What versions of PHP are affected by CVE-2026-46640?

This CVE affects Twig template engine versions 3.15.0 through 3.25.x when used with PHP. Any PHP installation using an affected Twig version is vulnerable, regardless of the PHP version itself.

How do I check if my server is vulnerable to CVE-2026-46640?

Run `php -r "echo Twig\\Environment::VERSION;"` to check your installed Twig version. If the version is between 3.15.0 and 3.25.x inclusive, your system is vulnerable and requires immediate patching to 3.26.0 or later.

Does Defensia detect CVE-2026-46640?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If PHP and Twig are installed on a monitored server, CVE-2026-46640 will appear in your dashboard with remediation steps.

Related PHP CVEs

CVE-2025-46348CVSS 10YesWiki is a wiki system written in PHP. Prior to version 4.5.4, the request to commence a site backup can be performed and downloaded without authentication. The archives are created with a predictable filename, so a malicious user could create and download an archive without being authenticated. This could result in a malicious attacker making numerous requests to create archives and fill up the file system, or by downloading the archive which contains sensitive site information. This issue has been patched in version 4.5.4.
CVE-2025-62521CVSS 10ChurchCRM is an open-source church management system. Prior to version 5.21.0, a pre-authentication remote code execution vulnerability in ChurchCRM's setup wizard allows unauthenticated attackers to inject arbitrary PHP code during the initial installation process, leading to complete server compromise. The vulnerability exists in `setup/routes/setup.php` where user input from the setup form is directly concatenated into a PHP configuration template without any validation or sanitization. Any parameter in the setup form can be used to inject PHP code that gets written to `Include/Config.php`, which is then executed on every page load. This is more severe than typical authenticated RCE vulnerabilities because it requires no credentials and affects the installation process that administrators must complete. Version 5.21.0 patches the issue.
CVE-2025-47916CVSS 10Invision Community 5.0.0 before 5.0.7 allows remote code execution via crafted template strings to themeeditor.php. The issue lies within the themeeditor controller (file: /applications/core/modules/front/system/themeeditor.php), where a protected method named customCss can be invoked by unauthenticated users. This method passes the value of the content parameter to the Theme::makeProcessFunction() method; hence it is evaluated by the template engine. Accordingly, this can be exploited by unauthenticated attackers to inject and execute arbitrary PHP code by providing crafted template strings.
CVE-2025-25174CVSS 10Improper Control of Filename for Include/Require Statement in PHP Program ('PHP Remote File Inclusion') vulnerability in beeteam368 BeeTeam368 Extensions beeteam368-extensions allows PHP Local File Inclusion.This issue affects BeeTeam368 Extensions: from n/a through <= 1.9.4.
CVE-2026-28289CVSS 10FreeScout is a free help desk and shared inbox built with PHP's Laravel framework. A patch bypass vulnerability for CVE-2026-27636 in FreeScout 1.8.206 and earlier allows any authenticated user with file upload permissions to achieve Remote Code Execution (RCE) on the server by uploading a malicious .htaccess file using a zero-width space character prefix to bypass the security check. The vulnerability exists in the sanitizeUploadedFileName() function in app/Http/Helper.php. The function contains a Time-of-Check to Time-of-Use (TOCTOU) flaw where the dot-prefix check occurs before sanitization removes invisible characters. This vulnerability is fixed in 1.8.207.

References

Track CVEs across your fleet automatically

Defensia scans your Linux servers and tells you exactly which ones are running vulnerable versions — including CVE-2026-46640. Free for 1 server.

Get started free