Twig: Sandbox resource exhaustion via unbounded `for` / `range()`
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-400.
Summary
Twig is a template language for PHP. Prior to 3.26.0, the Twig sandbox does not prevent a template from consuming CPU, memory, or wall-clock time, even under the strictest allow-list, allowing untrusted templates to cause resource exhaustion. This issue is addressed in version 3.26.0 by documenting that the sandbox does not protect against resource exhaustion.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
- Fix · CNA Twig (twigphp) Fixed in 3.26.0
Timeline
- 2026-10-02 Threatist record created from CVE-2026-46627
References
More symfony Twig vulnerabilities
- TI-2026-34283 Twig: The `spaceless` filter implicitly marks its output as safe CVSS 4.0MEDIUM 5.1
- TI-2022-07667 Code injection in Twig CVSS 3.1CRITICAL 9.8
- TI-2018-10028 Twig before 2.4.4 allows Server-Side Template Injection (SSTI) via the search search_key… CVSS 3.0CRITICAL 9.8
- TI-2022-18637 Twig may load a template outside a configured directory when using the filesystem loader CVSS 3.1HIGH 7.5
- TI-2026-34292 Twig: Arbitrary PHP code execution via `_self.(<string>)` macro-reference compilation CVSS 4.0HIGH 8.7
- TI-2026-34285 Twig: PHP code injection via `{% use %}` template name CVSS 4.0HIGH 8.7
Sources
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences