CVE-2026-71291
Bolt CMS Server-Side Template Injection via Unsandboxed allow_twig Field Rendering
Bolt CMS renders content field values through Twig's full application-level Environment with no SandboxExtension registered anywhere in the codebase. In src/Entity/Field.php, getTwigValue calls shouldBeRenderedAsTwig, which gates rendering only on the field definition's allow_twig flag and a regex checking for , , or ; when true, the raw field value is compiled and rendered via with no sandboxing.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
8.8
Bolt CMS Server-Side Template Injection via Unsandboxed allow_twig Field Rendering
Bolt CMS renders content field values through Twig's full application-level Environment with no SandboxExtension registered anywhere in the codebase. In src/Entity/Field.php, getTwigValue calls shouldBeRenderedAsTwig, which gates rendering only on the field definition's allow_twig flag and a regex checking for , , or ; when true, the raw field value is compiled and rendered via with no sandboxing.
- Record
CVE-2026-71291- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-1336
- Updated
- 2026-11-02
EUVDEUVD-2026-53376
8.8
Bolt CMS renders content field values through Twig's full application-level Environment with no SandboxExtension registered anywhere in the codebase. In src/Entity/Field.php, getTwigValue calls shouldBeRenderedAsTwig, which gates rendering only on the field definition's allow_twig flag and a regex checking for , , or ; when true, the raw field value is compiled and rendered via with no sandboxing.
- Record
EUVD-2026-53376- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-m6xj-xx3f-5vv9
8.8
Bolt CMS renders content field values through Twig's full application-level Environment with no...
Bolt CMS renders content field values through Twig's full application-level Environment with no SandboxExtension registered anywhere in the codebase. In src/Entity/Field.php, getTwigValue() calls shouldBeRenderedAsTwig(), which gates rendering only on the field definition's allow_twig flag and a regex checking for {{, {%, or {#; when true, the raw field value is compiled and rendered via self::getTwig()->createTemplate($value)->render(['record' => $this->getContent()]) with no sandboxing. Bolt's own bundled config/bolt/contenttypes.yaml sets allow_twig: true on the default "pages" contenttype's content field out of the box. Any user with edit access to that content type (a standard editor role, not just an administrator) can inject a Twig payload such as {{ ['id']|map('passthru')|join }} that executes arbitrary OS commands when the content is saved and rendered, achieving remote code execution as the web server user.
- Record
GHSA-m6xj-xx3f-5vv9- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-1336
- Updated
- 2026-11-02
NVD
8.8
Bolt CMS renders content field values through Twig's full application-level Environment with no SandboxExtension registered anywhere in the codebase. In src/Entity/Field.php, getTwigValue calls shouldBeRenderedAsTwig, which gates rendering only on the field definition's allow_twig flag and a regex checking for , , or ; when true, the raw field value is compiled and rendered via with no sandboxing.
- Record
CVE-2026-71291- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-1336
- Updated
- 2026-11-02
OSV
8.8
Bolt CMS Server-Side Template Injection via Unsandboxed allow_twig Field Rendering
Bolt CMS renders content field values through Twig's full application-level Environment with no SandboxExtension registered anywhere in the codebase. In src/Entity/Field.php, getTwigValue calls shouldBeRenderedAsTwig, which gates rendering only on the field definition's allow_twig flag and a regex checking for , , or ; when true, the raw field value is compiled and rendered via with no sandboxing.
- Record
CVE-2026-71291- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-1336
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-71291 is a high vulnerability (CVSS 8.8) in Bolt Core, published August 5, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.55%, the 46th percentile. No source names a fixed version.